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1

Development of an Enhanced GenVARR™ (Generator Volt Ampere Reactive Reserve) System  

SciTech Connect

Transmission system operators require near real time knowledge of reactive power capability to reliably operate large electric power transmission systems. Reactive power produced by, or capable of being produced by, a power generator is often estimated based on a series of mega volt amperes (MVA) capability curves for the generator. These curves indicate the ability of the generator to produce real and reactive power under a variety of conditions. In transmission planning and operating studies, it is often assumed, based on estimates for these capability curves, that the generator can provide its rated MVA capability output when needed for system stability However, generators may not always operate at levels depicted by the maximum MVA capability curve due to present constraints. Transmission system operators utilizing the generators’ capability curves for operation decisions regarding transmission system stability or for planning horizons may overestimate the capability of the generators to supply reactive power when required. Southern Company has enhanced GenVARR(TM), the system of plant data query, retrieval, and analysis and calculates the actual – not estimated -- remaining reactive power output capability. The remaining reactive output is considered spinning reserve and is displayed graphically to transmission control center and generating plant operators to identify real time VAR limits. GenVARR is capable of aggregating generators from a defined region, or other user selectable combinations, to represent the available reserves that the operators are specifically interested in. GenVARR(TM) has been put into live production operation and is expected to significantly improve the overall visibility of the reactive reserve capability of the system. This new version of GenVARR(TM) significantly enhances the products structure and performance, and enables links to other key transmission system operation tools.

Schatz, Joe E.

2009-03-12T23:59:59.000Z

2

Definition: Reactive Power | Open Energy Information  

Open Energy Info (EERE)

Reactive Power Reactive Power Jump to: navigation, search Dictionary.png Reactive Power The portion of electricity that establishes and sustains the electric and magnetic fields of alternating-current equipment. Reactive power must be supplied to most types of magnetic equipment, such as motors and transformers. It also must supply the reactive losses on transmission facilities. Reactive power is provided by generators, synchronous condensers, or electrostatic equipment such as capacitors and directly influences electric system voltage. It is usually expressed in kilovars (kvar) or megavars (Mvar).[1] View on Wikipedia Wikipedia Definition In electric power transmission and distribution, volt-ampere reactive (var) is a unit used to measure reactive power in an AC electric

3

4160 Volt .pdf  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

" " ~, U.S. Department of Energy Naval Reactors laboratory Field Office Knolls Laboratory National Environmental Policy Act (NEPA) Categorical Exclusion (CX) Determination Summary Form 4160 Volt Upgrade Project REFERENCE: 10 CFR Part 1021 , Department of Energy National Environmental Policy Act Implementation Procedures, Subpart 0 , Typical Classes of Actions PROJECT SCOPE DISCUSSION The scope of 4160 Volt Upgrade Project is to make significant improvements to the 4160 Volt power distribution system at the Knolls Laboratory by replacing antiquated (60 year old) switchgear and cabling located in the Z4 high yard with new state-of-the-art equipment. The new switch gear will be located in the NW corner of the existing Z8 High Yard. In addition to

4

Definition: Ampere | Open Energy Information  

Open Energy Info (EERE)

Definition Definition Edit with form History Facebook icon Twitter icon » Definition: Ampere Jump to: navigation, search Dictionary.png Ampere A unit of measure for electric current that refers to the amount of electric charge passing a point per unit of time; frequently abbreviated to "amp".[1][2] View on Wikipedia Wikipedia Definition The ampere, often shortened to amp, is the SI unit of electric current and is one of the seven SI base units. It is named after André-Marie Ampère (1775-1836), French mathematician and physicist, considered the father of electrodynamics. In practical terms, the ampere is a measure of the amount of electric charge passing a point in an electric circuit per unit time with 6.241 × 10 electrons, or one coulomb per second constituting one ampere. The practical definition may lead to

5

Sky Volt | Open Energy Information  

Open Energy Info (EERE)

Volt Volt Jump to: navigation, search Name Sky Volt Facility Sky Volt Sector Wind energy Facility Type Community Wind Facility Status In Service Owner Sky Volt LLC (community owned) Energy Purchaser City of Greenfield - excess to Central Iowa Power Cooperative Location Greenfield IA Coordinates 41.29038343°, -94.48851585° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":41.29038343,"lon":-94.48851585,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

6

Glossary Item - Electron Volt (eV)  

NLE Websites -- All DOE Office Websites (Extended Search)

Electron Volt (eV) An electron volt is the amount of work done on an electron when it moves through a potential difference of one volt. 1 eV 1.602*10-19 J 1.602*10-12 erg ...

7

Amper Central Solar SA | Open Energy Information  

Open Energy Info (EERE)

Central Solar SA Place Moura, Portugal Zip 7860 231 Sector Solar Product Portugal-based solar PV project developer. References Amper Central Solar SA1 LinkedIn Connections...

8

AdaptiVolt(TM) Technology Assessment Report  

Science Conference Proceedings (OSTI)

A technology assessment was conducted for AdaptiVolt and Line Drop Compensation (LDC) technologies for reducing energy consumption and demand by controlling feeder voltage.

2009-03-30T23:59:59.000Z

9

CODATA Value: electron volt-hertz relationship  

Science Conference Proceedings (OSTI)

... electron volt-hertz relationship. Value, 2.417 989 348 x 10 14 Hz. Standard uncertainty, 0.000 000 053 x 10 14 Hz. Relative ...

10

CODATA Value: electron volt-hartree relationship  

Science Conference Proceedings (OSTI)

... electron volt-hartree relationship. Value, 3.674 932 379 x 10 -2 E h. Standard uncertainty, 0.000 000 081 x 10 -2 E h. Relative ...

11

GreenVolts Inc | Open Energy Information  

Open Energy Info (EERE)

of concentrating PV (CPV). References GreenVolts Inc1 LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now This article is a stub. You can help OpenEI...

12

EV Project Chevrolet Volt Vehicle Summary Report  

NLE Websites -- All DOE Office Websites (Extended Search)

events 72% 10% 18% 2011 ECOtality 2132012 2:44:55 PM INLMIS-11-24041 Page 1 of 3 EV Project Chevrolet Volt Vehicle Summary Report Region: Houston, TX Metropolitan Area...

13

EV Project Chevrolet Volt Vehicle Summary Report  

NLE Websites -- All DOE Office Websites (Extended Search)

events (mi) 25.8 Avg number of charging events per day when the vehicle was driven 1.4 EV Project Chevrolet Volt Vehicle Summary Report Region: Phoenix, AZ Metropolitan Area...

14

EV Project Chevrolet Volt Vehicle Summary Report  

NLE Websites -- All DOE Office Websites (Extended Search)

data anomalies. 2012 ECOtality 10232012 2:02:15 PM INLMIS-11-24041 Page 1 of 12 EV Project Chevrolet Volt Vehicle Summary Report Region: Phoenix, AZ Metropolitan Area...

15

EV Project Chevrolet Volt Vehicle Summary Report  

NLE Websites -- All DOE Office Websites (Extended Search)

GPS data anomalies. 2012 ECOtality 532012 5:28:32 PM INLMIS-11-24041 Page 1 of 8 EV Project Chevrolet Volt Vehicle Summary Report Region: Oregon Number of vehicles: 23...

16

GreenVolts | Open Energy Information  

Open Energy Info (EERE)

GreenVolts GreenVolts Jump to: navigation, search Logo: GreenVolts Name GreenVolts Address 50 First Street Place San Francisco, California Zip 94105 Sector Solar Product PV developer Website http://www.greenvolts.com/ Coordinates 37.790153°, -122.398669° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":37.790153,"lon":-122.398669,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

17

Multipacting analysis for JLAB ampere class cavities  

SciTech Connect

JLAB's ampere class 5-cell cavities require a moderate accelerating gradient (16.7 {approx} 20MV/m). Electron multipacting activity in the machine operating range can degrade the expected performance. A survey was conducted in the area of multipacting analysis for beta=1 electron cavity shapes, including options for the new high current cavity shape. The results obtained provided useful guidance to the final cavity shape adopted and to its expected performance.

Genfa Wu; Mircea Stirbet; Haipeng Wang; Robert Rimmer; Evan Donoghue

2005-07-10T23:59:59.000Z

18

The Josephson Volt: NIST's First Quantum Electrical Standard  

Science Conference Proceedings (OSTI)

The Josephson Volt: NIST's First Quantum Electrical Standard. Purpose: The development of voltage standards based on ...

2011-11-21T23:59:59.000Z

19

HelioVolt Corporation | Open Energy Information  

Open Energy Info (EERE)

HelioVolt Corporation HelioVolt Corporation Jump to: navigation, search Name HelioVolt Corporation Place Austin, Texas Zip TX 78744 Product Copper indium gallium selenide (CIGS) thin-film PV module manufacturer based in Austin, Texas. Website http://www.heliovolt.net/ Coordinates 30.267605°, -97.742984° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":30.267605,"lon":-97.742984,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

20

HydroVolts | Open Energy Information  

Open Energy Info (EERE)

HydroVolts HydroVolts Jump to: navigation, search Name HydroVolts Address 2815 Eastlake Ave E Place Seattle, Washington Zip 98102 Sector Hydro Product Aims to develop renewable energy from canals, waterways, streams, and ocean currents Website http://www.hydrovolts.com/ Coordinates 47.645778°, -122.3257532° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":47.645778,"lon":-122.3257532,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

A Tariff for Reactive Power  

DOE Green Energy (OSTI)

Two kinds of power are required to operate an electric power system: real power, measured in watts, and reactive power, measured in volt-amperes reactive or VARs. Reactive power supply is one of a class of power system reliability services collectively known as ancillary services, and is essential for the reliable operation of the bulk power system. Reactive power flows when current leads or lags behind voltage. Typically, the current in a distribution system lags behind voltage because of inductive loads such as motors. Reactive power flow wastes energy and capacity and causes voltage droop. To correct lagging power flow, leading reactive power (current leading voltage) is supplied to bring the current into phase with voltage. When the current is in phase with voltage, there is a reduction in system losses, an increase in system capacity, and a rise in voltage. Reactive power can be supplied from either static or dynamic VAR sources. Static sources are typically transmission and distribution equipment, such as capacitors at substations, and their cost has historically been included in the revenue requirement of the transmission operator (TO), and recovered through cost-of-service rates. By contrast, dynamic sources are typically generators capable of producing variable levels of reactive power by automatically controlling the generator to regulate voltage. Transmission system devices such as synchronous condensers can also provide dynamic reactive power. A class of solid state devices (called flexible AC transmission system devices or FACTs) can provide dynamic reactive power. One specific device has the unfortunate name of static VAR compensator (SVC), where 'static' refers to the solid state nature of the device (it does not include rotating equipment) and not to the production of static reactive power. Dynamic sources at the distribution level, while more costly would be very useful in helping to regulate local voltage. Local voltage regulation would reduce system losses, increase circuit capacity, increase reliability, and improve efficiency. Reactive power is theoretically available from any inverter-based equipment such as photovoltaic (PV) systems, fuel cells, microturbines, and adjustable-speed drives. However, the installation is usually only economical if reactive power supply is considered during the design and construction phase. In this report, we find that if the inverters of PV systems or the generators of combined heat and power (CHP) systems were designed with capability to supply dynamic reactive power, they could do this quite economically. In fact, on an annualized basis, these inverters and generators may be able to supply dynamic reactive power for about $5 or $6 per kVAR. The savings from the local supply of dynamic reactive power would be in reduced losses, increased capacity, and decreased transmission congestion. The net savings are estimated to be about $7 per kVAR on an annualized basis for a hypothetical circuit. Thus the distribution company could economically purchase a dynamic reactive power service from customers for perhaps $6/kVAR. This practice would provide for better voltage regulation in the distribution system and would provide an alternate revenue source to help amortize the cost of PV and CHP installations. As distribution and transmission systems are operated under rising levels of stress, the value of local dynamic reactive supply is expected to grow. Also, large power inverters, in the range of 500 kW to 1 MW, are expected to decrease in cost as they become mass produced. This report provides one data point which shows that the local supply of dynamic reactive power is marginally profitable at present for a hypothetical circuit. We expect that the trends of growing power flow on the existing system and mass production of inverters for distributed energy devices will make the dynamic supply of reactive power from customers an integral component of economical and reliable system operation in the future.

Kueck, John D [ORNL; Kirby, Brendan J [ORNL; Li, Fangxing [ORNL; Tufon, Christopher [Pacific Gas and Electric Company; Isemonger, Alan [California Independent System Operator

2008-07-01T23:59:59.000Z

22

Chevy Volt Electrifies DOE Headquarters | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Chevy Volt Electrifies DOE Headquarters Chevy Volt Electrifies DOE Headquarters Chevy Volt Electrifies DOE Headquarters December 9, 2010 - 7:05pm Addthis Dennis A. Smith Director, National Clean Cities Yesterday, Department of Energy staff members were able to experience the newest in market-ready vehicle technology when representatives from General Motors brought two Chevy Volts to Department headquarters. Officials and engineers alike, including the Department's Chief Financial Officer, Steve Isakowitz, test drove the Volt, and peppered the GM representatives with questions about the new plug-in hybrid electric vehicle. Unlike an all-electric vehicle (EV), the Volt has a gasoline engine that supplements the electric drive once the battery is depleted. The Chevrolet Volt will reach an estimated 93 mpg-equivalent when running on all-electric

23

HelioVolt Inc | Open Energy Information  

Open Energy Info (EERE)

Inc Inc Jump to: navigation, search Name HelioVolt Inc Address 8201 E. Riverside Dr Place Austin, Texas Zip 78744 Sector Solar Product Thin-film solar panel producer Website http://www.heliovolt.net/ Coordinates 30.216908°, -97.685078° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":30.216908,"lon":-97.685078,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

24

Microsoft Word - Efficiency Results of the Chevrolet Volt On...  

NLE Websites -- All DOE Office Websites (Extended Search)

INLEXT-12-25761 Advanced Vehicle Testing Activity Benchmark Testing of the Chevrolet Volt Onboard Charger Richard "Barney" Carlson April 2012 DISCLAIMER This information was...

25

SeaVolt Technologies formerly Sea Power Associates | Open Energy  

Open Energy Info (EERE)

SeaVolt Technologies formerly Sea Power Associates SeaVolt Technologies formerly Sea Power Associates Jump to: navigation, search Name SeaVolt Technologies (formerly Sea Power & Associates) Place San Francisco, California Zip CA 94111 Sector Ocean Product The company's Wave Rider system, which is still in prototype stages, uses buoys and hydraulic pumps to convert the movement of ocean waves into electricity. References SeaVolt Technologies (formerly Sea Power & Associates)[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This company is listed in the Marine and Hydrokinetic Technology Database. This article is a stub. You can help OpenEI by expanding it. SeaVolt Technologies (formerly Sea Power & Associates) is a company located in San Francisco, California .

26

The Department of Energy's Innovation in GM's Chevrolet Volt | Department  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

The Department of Energy's Innovation in GM's Chevrolet Volt The Department of Energy's Innovation in GM's Chevrolet Volt The Department of Energy's Innovation in GM's Chevrolet Volt January 11, 2011 - 11:49am Addthis Chevy Volt and replica battery | Photo Courtesy of Argonne Lab's Flickr Chevy Volt and replica battery | Photo Courtesy of Argonne Lab's Flickr Patrick B. Davis Patrick B. Davis Vehicle Technologies Program Manager Last Thursday was a big day in the world of advanced vehicle batteries. On January 6, the Department of Energy's Argonne National Laboratory announced that General Motors and its battery cell supplier, LG Chem Power Inc., have each signed licensing agreements to use Argonne's breakthrough battery technology. Funded by the Department, scientists at Argonne have developed a unique suite of cathode materials - a 'family' of lithium-rich

27

The Department of Energy's Innovation in GM's Chevrolet Volt | Department  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Innovation in GM's Chevrolet Volt Innovation in GM's Chevrolet Volt The Department of Energy's Innovation in GM's Chevrolet Volt January 11, 2011 - 11:49am Addthis Chevy Volt and replica battery | Photo Courtesy of Argonne Lab's Flickr Chevy Volt and replica battery | Photo Courtesy of Argonne Lab's Flickr Patrick B. Davis Patrick B. Davis Vehicle Technologies Program Manager Last Thursday was a big day in the world of advanced vehicle batteries. On January 6, the Department of Energy's Argonne National Laboratory announced that General Motors and its battery cell supplier, LG Chem Power Inc., have each signed licensing agreements to use Argonne's breakthrough battery technology. Funded by the Department, scientists at Argonne have developed a unique suite of cathode materials - a 'family' of lithium-rich

28

Nissan Leafs and Chevrolet Volts Reporting Data in The EV Project  

NLE Websites -- All DOE Office Websites (Extended Search)

Nissan Leafs and Chevrolet Volts Reporting Data in The EV Project Project to Date through June 2012 Washington State 700 Leafs 55 Volts Oregon 429 Leafs 59 Volts San Francisco 1307...

29

Nissan Leafs and Chevrolet Volts Reporting Data in The EV Project...  

NLE Websites -- All DOE Office Websites (Extended Search)

Leafs and Chevrolet Volts Reporting Data in The EV Project Project to Date through December 2012 Washington State 893 Leafs 98 Volts Oregon 549 Leafs 94 Volts 30 Smart Electric...

30

Argonne battery technology helps power Chevy Volt | Argonne National...  

NLE Websites -- All DOE Office Websites (Extended Search)

Argonne battery technology helps power Chevy Volt Intense, in-situ X-rays from the Advanced Photon Source at Argonne were used to help Argonne National Laboratory design the...

31

NREL Partnering with GreenVolts to Commercialize IMM Solar Cell  

NREL Partnering with GreenVolts to Commercialize IMM Solar Cell March 31, 2009. NREL is partnering with GreenVolts to commercialize the Inverted ...

32

Electrolytic cell. [operation at 500,000 amperes  

SciTech Connect

A novel electrolytic cell of the vertical electrode type comprising a novel cathode busbar structure, novel cathode elements and a novel anode base structure which enable the novel electrolytic cell to be designed to operate at high current capacities upward to about 500,000 amperes while maintaining high operating efficiencies is claimed. These high current capacities provide for high production capacities which result in high production rates for given cell room floor areas and reduce capital investment and operating costs.

Mose, L.; Kramer, W.; Strewe, W.; Strasser, B.

1977-04-12T23:59:59.000Z

33

CyVolt Energy Systems | Open Energy Information  

Open Energy Info (EERE)

CyVolt Energy Systems CyVolt Energy Systems Jump to: navigation, search Name CyVolt Energy Systems Place Seattle, Washington Zip 98104 Product Seattle-based developer fuel cell-powered battery systems for portable, hand-held consumer electronics Coordinates 47.60356°, -122.329439° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":47.60356,"lon":-122.329439,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

34

AMPERE AVERAGE CURRENT PHOTOINJECTOR AND ENERGY RECOVERY LINAC.  

SciTech Connect

High-power Free-Electron Lasers were made possible by advances in superconducting linac operated in an energy-recovery mode. In order to get to much higher power levels, say a fraction of a megawatt average power, many technological barriers are yet to be broken. We describe work on CW, high-current and high-brightness electron beams. This will include a description of a superconducting, laser-photocathode RF gun employing a new secondary-emission multiplying cathode, an accelerator cavity, both capable of producing of the order of one ampere average current and plans for an ERL based on these units.

BEN-ZVI,I.; BURRILL,A.; CALAGA,R.; ET AL.

2004-08-17T23:59:59.000Z

35

ELECTROSTATIC PROBE DIAGNOSTICS ON THE LBL 10 AMPERE NEUTRAL BEAM ION SOURCE  

E-Print Network (OSTI)

I/sec • J L P O E BIAS (VOLTS) R B XBL 786-9247 F i g u rusec over a total range of 100 volts are typical. The probea voltage resolution of 1/2 volt for a constant sweep speed

Schoenberg, Kurt F.

2011-01-01T23:59:59.000Z

36

Guidelines for Working at Voltages < 240 Volts  

NLE Websites -- All DOE Office Websites (Extended Search)

Guidelines for Working at Voltages < 240 Volts Guidelines for Working at Voltages < 240 Volts February 4, 2005---DRAFT NOTE: Working hot is a LAST ALTERNATIVE. Electrical hot work is defined as: Working on or near exposed conducting parts that are or might become energized at 50V or more. Refer to Electrical Safety Flowchart for Working On or Near Live Parts. Engineered methods to prevent exposed sources of 50V and greater are to be implemented wherever practical. Only QUALIFIED PERSONNEL {as defined in NFPA 70E Article 110.6(D) 2004 edition} as authorized by the CAT/supervisor/division can perform such work. Refer to Qualified Electrical Worker Flow Chart. Training requirements: ES&H 114 (LOTO) / ES&H 375 (NFPA 70E) / ES&H 371 (electrical worker) - Observe Electrical Safe Work Practices. Refer to

37

Distribution Efficiency: Modeling, Volt-Var Control, and Economics  

Science Conference Proceedings (OSTI)

As utilities strive to better utilize their distribution system assets and improve energy efficiency, improved distribution modeling and better economic models can help quantify economic gains. In order to improve efficiency modeling and economic planning, research efforts in this report have concentrated on the following tasks: distribution modeling for efficiency studies, volt-var control, and development of a framework to evaluate the economic benefit of reductions in average and peak energy reduction...

2010-12-31T23:59:59.000Z

38

Nissan Leafs and Chevrolet Volts Reporting Data in The EV Project  

NLE Websites -- All DOE Office Websites (Extended Search)

Idaho National Laboratory 10162012 INLMIS-12-26075 Nissan Leafs and Chevrolet Volts Reporting Data in The EV Project...

39

Nissan Leafs and Chevrolet Volts Reporting Data in The EV Project  

NLE Websites -- All DOE Office Websites (Extended Search)

Idaho National Laboratory 662012 INLMIS-12-26075 Nissan Leafs and Chevrolet Volts Reporting Data in The EV Project...

40

Particle physicist's dreams about PetaelectronVolt laser plasma accelerators  

Science Conference Proceedings (OSTI)

Present day accelerators are working well in the multi TeV energy scale and one is expecting exciting results in the coming years. Conventional technologies, however, can offer only incremental (factor 2 or 3) increase in beam energies which does not follow the usual speed of progress in the frontiers of high energy physics. Laser plasma accelerators theoretically provide unique possibilities to achieve orders of magnitude increases entering the PetaelectronVolt (PeV) energy range. It will be discussed what kind of new perspectives could be opened for the physics at this new energy scale. What type of accelerators would be required?.

Vesztergombi, G. [KFKI-RMKI. 1525-H Budapest P.O.B. 49. (Hungary)

2012-07-09T23:59:59.000Z

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Broad-beam multi-ampere metal ion source  

SciTech Connect

An embodiment of the MEVVA (metal vapor vacuum arc) high current metal ion source has been developed in which the beam is formed from a 10-cm diameter set of extractor grids and which produces a peak beam current of up to several Amperes. The source, MEVVA V, operates in a pulsed mode with a pulse width at present 0.25 ms and a repetition rate of up to several tens of pulses per second (power supply limited). The multicathode feature that was developed for the prior source version, MEVVA IV, has been incorporated here also; one can switch between any of 18 separate cathodes and thus metallic beam species. Maximum beam extraction voltage is over 90 kV, and since the ion charge state typically from Q = 1 to 5, depending on the metal employed, the ion energy in the extracted beam can thus be up to several hundred keV. This source is a new addition to the MEVVA family of metal ion sources, and we are at present investigating the operational regimes and the limits to the source performance. In this paper we describe the source and present some preliminary results. 10 refs., 4 figs.

Brown, I.G.; Galvin, J.E.; MacGill, R.A.; Paoloni, F.J. (Lawrence Berkeley Lab., CA (USA); Wollongong Univ. (Australia). Dept. of Electrical Engineering)

1989-06-01T23:59:59.000Z

42

The Breakthrough Behind the Chevy Volt Battery | U.S. DOE Office of Science (SC)  

NLE Websites -- All DOE Office Websites (Extended Search)

The Breakthrough Behind the Chevy Volt Battery The Breakthrough Behind the Chevy Volt Battery Stories of Discovery & Innovation The Breakthrough Behind the Chevy Volt Battery Enlarge Photo Image courtesy of General Motors The 2011 Chevrolet Volt's 16 kWh battery can be recharged using a 120V or 240V outlet. The car's lithium-ion battery is based on technology developed at Argonne National Laboratory. Enlarge Photo Illustration courtesy Argonne National Laboratory This illustration shows the inner workings of a lithium-ion battery. When delivering energy to a device, the lithium ion moves from the anode to the cathode. The ion moves in reverse when recharging. Compared to other rechargeable 03.28.11 The Breakthrough Behind the Chevy Volt Battery A revolutionary breakthrough cathode for lithium-ion batteries-the kind in your

43

STATEMENT OF CONSIDERATIONS REQUEST BY SOUTHERN COMPANY SERVICES...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

AGREEMENT NO. DE-FC02-05CH11327 ENTITLED "DEVELOPMENT OF THE UPGRADE OF THE GENERATOR VOLT AMPERE REACTIVE RESERVE (GENVARR) SYSTEM;" W(A)-05-051; CH-1338 As set out in the...

44

Energy Ef?cient Hybrid Silicon Electroabsorption Modulator for 40 Gb/s, 1-Volt Uncooled Operation  

E-Print Network (OSTI)

er 10.1109/LPT.2012.2212702 1-volt operation at 25 Gb/s hasmodulator with a sub-volt drive voltage swing for 10 Gb/sto around 30 GHz and 1-volt operation at 40 Gb/s is

Tang, Yongbo; Peters, Jonathan; Bowers, John E

2012-01-01T23:59:59.000Z

45

Advanced Vehicle Testing Activity Benchmark Testing of the Chevrolet Volt Onboard Charger  

DOE Green Energy (OSTI)

This is a report for public consumption, for the AVTA website, detailing the testing and analysis of the benchmark testing conducted on the Chevrolet Volt on-board charger.

Richard Carlson

2012-04-01T23:59:59.000Z

46

How much are Chevrolet Volts in The EV Project driven in EV Mode?  

Science Conference Proceedings (OSTI)

This report summarizes key conclusions from analysis of data collected from Chevrolet Volts participating in The EV Project. Topics include how many miles are driven in EV mode, how far vehicles are driven between charging events, and how much energy is charged from the electric grid per charging event.

John Smart

2013-08-01T23:59:59.000Z

47

Glossary - U.S. Energy Information Administration (EIA)  

U.S. Energy Information Administration (EIA)

Kilovolt-Ampere (kVa): A unit of apparent power, equal to 1,000 volt-amperes; the mathematical product of the volts and amperes in an electrical circuit.

48

Case Study on Conservation Voltage Reduction and Volt-VAR Optimization: Sacramento Municipal Utility District  

Science Conference Proceedings (OSTI)

As part of its SmartSacramento® Project, SMUD tested two control strategies for improving distribution efficiency: conservation voltage reduction (CVR) and volt-VAR optimization (VVO).  SMUD, in conjunction with The Structure Group, enhanced existing control logic and developed new control logic to implement these two control strategies via SMUD’s existing Siemens SCADA system.This case study presents results of a SMUD  pilot in the summer of 2011 to demonstrate the ...

2012-10-31T23:59:59.000Z

49

Engineering Design and Fabrication of an Ampere-Class Superconducting Photocathode Electron Gun  

SciTech Connect

Over the past three years, Advanced Energy Systems and Brookhaven National Laboratory (BNL) have been collaborating on the design of an Ampere- class superconducting photocathode electron gun. BNL performed the physics design of the overall system and RF cavity under prior programs. Advanced Energy Systems (AES) is currently responsible for the engineering design and fabrication of the electron gun under contract to BNL. We will report on the engineering design and fabrication status of the superconducting photocathode electron gun. The overall configuration of the cryomodule will be reviewed. The layout of the hermitic string, space frame, shielding package, and cold mass will be discussed. The engineering design of the gun cavity and removable cathode will be presented in detail and areas of technical risk will be highlighted. Finally, the fabrication sequence and fabrication status of the gun cavity will be discussed.

Ben-Zvi,I.

2008-11-17T23:59:59.000Z

50

Toroidal ripple transport of beam ions in the mega-ampere spherical tokamak  

Science Conference Proceedings (OSTI)

The transport of injected beam ions due to toroidal magnetic field ripple in the mega-ampere spherical tokamak (MAST) is quantified using a full orbit particle tracking code, with collisional slowing-down and pitch-angle scattering by electrons and bulk ions taken into account. It is shown that the level of ripple losses is generally rather low, although it depends sensitively on the major radius of the outer midplane plasma edge; for typical values of this parameter in MAST plasmas, the reduction in beam heating power due specifically to ripple transport is less than 1%, and the ripple contribution to beam ion diffusivity is of the order of 0.1 m{sup 2} s{sup -1} or less. It is concluded that ripple effects make only a small contribution to anomalous transport rates that have been invoked to account for measured neutron rates and plasma stored energies in some MAST discharges. Delayed (non-prompt) losses are shown to occur close to the outer midplane, suggesting that banana-drift diffusion is the most likely cause of the ripple-induced losses.

McClements, K. G. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom); Hole, M. J. [Plasma Research Laboratory, Research School of Physical Science and Engineering, Australian National University, Canberra, ACT 0200 (Australia)

2012-07-15T23:59:59.000Z

51

2011 Chevrolet Volt VIN 0815 Plug-In Hybrid Electric Vehicle Battery Test Results  

SciTech Connect

The U.S. Department of Energy (DOE) Advanced Vehicle Testing Activity (AVTA) program consists of vehicle, battery, and infrastructure testing on advanced technology related to transportation. The activity includes tests on plug-in hybrid electric vehicles (PHEVs), including testing the PHEV batteries when both the vehicles and batteries are new and at the conclusion of 12,000 miles of on-road fleet testing. This report documents battery testing performed for the 2011 Chevrolet Volt PHEV (VIN 1G1RD6E48BU100815). The battery testing was performed by the Electric Transportation Engineering Corporation (eTec) dba ECOtality North America. The Idaho National Laboratory and ECOtality North America collaborate on the AVTA for the Vehicle Technologies Program of the DOE.

Tyler Gray; Matthew Shirk; Jeffrey Wishart

2013-07-01T23:59:59.000Z

52

Implementing Distribution Performance Optimization Functions That Integrate with Advanced Metering  

Science Conference Proceedings (OSTI)

This report presents the results of a study of how the data and networks of advanced metering infrastructure (AMI) might be used to benefit Volt/Volt-ampere-reactive (VAR) control. It includes a detailed overview of integrated Volt/VAR control and an in-depth assessment of how the use of AMI might be able to assist in the performance of the common tasks required. Sample case studies are provided, showing practical examples of systems currently implemented. Providers of Volt/VAR control systems were invit...

2010-12-31T23:59:59.000Z

53

Hydro-Quebec Smart Grid Host Site Progress Report  

Science Conference Proceedings (OSTI)

This report is a progress update on the Hydro-Qubec (H-Q) Smart Grid Demonstration Project. This project is part of the Electric Power Research Institute's (EPRI's) multi-year Smart Grid Demonstration Initiative. The project focuses on volt and volt-ampere reactive (VAR) control (VVC), distribution automation (DA), advanced metering infrastructure (AMI), automatic fault location, wireless communication, and electric vehicle (EV) infrastructure.

2012-02-02T23:59:59.000Z

54

Optimization of Solar Cell Design for Use with GreenVolts CPV System: Cooperative Research and Development Final Report, CRADA Number CRD-08-00281  

DOE Green Energy (OSTI)

GreenVolts, a Bay area start-up, was developing a CPV system that was based on a unique reflective optical design. They were interested in adapting the inverted GaInP/GaAs/GaInAs cell structure designed at NREL for use in their system. The purpose of this project was to optimize the inverted GaInP/GaAs/GaInAs cell for operation in the GreenVolts optical system.

Ward, S.

2011-05-01T23:59:59.000Z

55

ESB Networks Case Study on Distribution Volt-VAR Control Integrated with Wind Turbine Inverter Control  

Science Conference Proceedings (OSTI)

The key topic addressed in this Smart Grid Demonstration case study is how the decoupled reactive power capability of modern, doubly fed induction generator (DFIG) wind farms can be used to actively control voltage at the point of common coupling. This was done within the context of assessing technologies that will allow higher penetration of renewable resources without violating voltage limits on local distribution systems.A trial was conducted, using a section of Ireland’s ESB ...

2012-12-31T23:59:59.000Z

56

Detection of atomic and molecular mega-electron-volt projectiles using an x-ray charged coupled device camera  

SciTech Connect

We show that an x-ray charge coupled device (CCD) may be used as a particle detector for atomic and molecular mega-electron-volt (MeV) projectiles of around a few hundred keV per atomic mass unit. For atomic species, spectroscopic properties in kinetic energy measurements (i.e., linearity and energy resolution) are found to be close to those currently obtained with implanted or surface barrier silicon particle detectors. For molecular species, in order to increase the maximum kinetic energy detection limit, we propose to put a thin foil in front of the CCD. This foil breaks up the molecules into atoms and spreads the charges over many CCD pixels and therefore avoiding saturation effects. This opens new perspectives in high velocity molecular dissociation studies with accelerator facilities.

Chabot, M.; Martinet, G.; Bouneau, S.; Genolini, B.; Grave, X.; Nguyen, K.; Le Gailliard, C.; Rosier, P. [Institut de Physique Nucleaire d'Orsay, IN2P3-CNRS, Universite Paris Sud, 91406 Orsay cedex (France); Beroff, K.; Pino, T.; Feraud, G.; Friha, H. [Institut des Sciences Moleculaires d'Orsay, INP-CNRS, Universite Paris Sud, 91406 Orsay cedex (France); Villier, B. [Hamamatsu Photonics (France)

2011-10-15T23:59:59.000Z

57

Flicker Control of Car Shredder Using Hybrid VAR Compensator  

Science Conference Proceedings (OSTI)

The different operating modes of a new car shredder were anticipated to produce significant voltage drop across the electrical supply network, resulting in flicker emissions that would cause the planning levels at PCC to exceed the limits recommended by the International Electrotechnical Commission. Hand calculations were used to estimate the voltage drop for the various modes and the reactive compensation required to keep flicker at acceptable levels. A hybrid volt-ampere-reactive compensator was design...

2011-12-30T23:59:59.000Z

58

Impacts of Varying Penetration of Distributed Resources with & without Volt/Var Control: Case Study of Varying Load Types  

SciTech Connect

This paper provides a follow-up to an earlier one on impacts of distributed energy resources (DR) on distribution feeders. As DR penetration level on the feeder increases, there can be impacts to distribution system/feeder capacity, line losses, and voltage regulation. These can vary as the penetration level reaches the capacity of the distribution feeder/system or loading. The question is how high of a DR level can be accommodated without any major changes to system operation, system design and protection. Our objective for this work was to address the question of how the DR impacts vary in regards to both DR voltage regulation capability and load mix. A dynamic analysis was used to focus on the impacts of DR with and without volt/var control with different load composition on the distribution feeder. The study considered an example 10MVA distribution feeder in which two inverter-based DRs were used to provide voltage regulation. The results due to DR without voltage regulation capability are compared with DR capable of providing local (at its bus) voltage regulation. The analysis was repeated for four different feeder load compositions consisting of (1) constant power, (2) constant impedance, (3) constant current and (4) ZIP (equal combination of previous three).

Rizy, D Tom [ORNL; Li, Huijuan [ORNL; Li, Fangxing [ORNL; Xu, Yan [ORNL; Adhikari, Sarina [ORNL; Irminger, Philip [ORNL

2011-01-01T23:59:59.000Z

59

Chevrolet Volt Vehicle Demonstration  

NLE Websites -- All DOE Office Websites (Extended Search)

2012 Number of vehicles: 143 Number of vehicle days driven: 6,598 All operation Overall gasoline fuel economy (mpg) 73.7 Overall AC electrical energy consumption (AC Whmi) 170...

60

Chevrolet Volt Vehicle Demonstration  

NLE Websites -- All DOE Office Websites (Extended Search)

2012 Number of vehicles: 145 Number of vehicle days driven: 6,817 All operation Overall gasoline fuel economy (mpg) 66.6 Overall AC electrical energy consumption (AC Whmi) 171...

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Chevrolet Volt Vehicle Demonstration  

NLE Websites -- All DOE Office Websites (Extended Search)

2011 Number of vehicles: 135 Number of vehicle days driven: 4,746 All operation Overall gasoline fuel economy (mpg) 68.6 Overall AC electrical energy consumption (AC Whmi) 175...

62

Chevrolet Volt Vehicle Demonstration  

NLE Websites -- All DOE Office Websites (Extended Search)

June 2011 Number of vehicles: 66 Number of vehicle days driven: 845 All operation Overall gasoline fuel economy (mpg) 85.0 Overall AC electrical energy consumption (AC Whmi) 181...

63

Chevrolet Volt Vehicle Demonstration  

NLE Websites -- All DOE Office Websites (Extended Search)

355,058 Average Ambient Temperature (deg F) 46.0 Electric Vehicle mode operation (EV) Gasoline fuel economy (mpg) No Fuel Used AC electrical energy consumption (AC Whmi) 416...

64

Chevrolet Volt Vehicle Demonstration  

NLE Websites -- All DOE Office Websites (Extended Search)

2,405,406 Average Ambient Temperature (deg F) 61.4 Electric Vehicle mode operation (EV) Gasoline fuel economy (mpg) No Fuel Used AC electrical energy consumption (AC Whmi) 355...

65

Chevrolet Volt Vehicle Demonstration  

NLE Websites -- All DOE Office Websites (Extended Search)

2012 Number of vehicles: 143 Number of vehicle days driven: 5,795 All operation Overall gasoline fuel economy (mpg) 67.8 Overall AC electrical energy consumption (AC Whmi) 180...

66

Chevrolet Volt Vehicle Demonstration  

NLE Websites -- All DOE Office Websites (Extended Search)

2011 Number of vehicles: 110 Number of vehicle days driven: 3,227 All operation Overall gasoline fuel economy (mpg) 74.8 Overall AC electrical energy consumption (AC Whmi) 185...

67

Chevrolet Volt Vehicle Demonstration  

NLE Websites -- All DOE Office Websites (Extended Search)

2012 Number of vehicles: 144 Number of vehicle days driven: 7,129 All operation Overall gasoline fuel economy (mpg) 72.5 Overall AC electrical energy consumption (AC Whmi) 166...

68

Life Extension Guidelines for Static VAR Compensators  

Science Conference Proceedings (OSTI)

The static volt-ampere-reactive (VAR) compensator (SVC) was first introduced in the early 1960s in the form of mechanically switched saturated reactors and capacitors. In the 1970s, thyristor-controlled reactors and capacitors were introduced, overcoming technical limitations of saturable reactors by offering dynamic switching. As with many other parts of the utility infrastructure, these SVCs are reaching the end of their service lifetime. Owners/operators need help making maintenance and replacement/re...

2009-11-06T23:59:59.000Z

69

Assessment of Retrofit Energy Savings Devices: KVAR Energy Controller  

Science Conference Proceedings (OSTI)

This report describes and documents the performance of the kilovolt ampere reactive (KVAR) energy controller by KVAR Energy Savings Corporation. The specific part number tested was the PU-1200. This device is a 240-volt unit designed for installation at the residential customer's breaker panel. As of August 26, 2010, energy savings claims for the residential application of this device range from 6% to 10%, as indicated on KVAR's website. Various product distributors claim similar or greater savings on th...

2010-09-14T23:59:59.000Z

70

System for reactivating catalysts  

DOE Patents (OSTI)

A method of reactivating a catalyst, such as a solid catalyst or a liquid catalyst is provided. The method comprises providing a catalyst that is at least partially deactivated by fouling agents. The catalyst is contacted with a fluid reactivating agent that is at or above a critical point of the fluid reactivating agent and is of sufficient density to dissolve impurities. The fluid reactivating agent reacts with at least one fouling agent, releasing the at least one fouling agent from the catalyst. The at least one fouling agent becomes dissolved in the fluid reactivating agent and is subsequently separated or removed from the fluid reactivating agent so that the fluid reactivating agent may be reused. A system for reactivating a catalyst is also disclosed.

Ginosar, Daniel M. (Idaho Falls, ID); Thompson, David N. (Idaho Falls, ID); Anderson, Raymond P. (Idaho Falls, ID)

2010-03-02T23:59:59.000Z

71

Energetical factors in power systems with nonlinear loads  

Science Conference Proceedings (OSTI)

Based on the volt-ampere charac- teristic of the nonlinear load, an equivalent circuit, containing linear elements, can be determined. In this way, load-flow and.

72

Experimentation and Measurement  

Science Conference Proceedings (OSTI)

... the following words: degree Fahrenheit; inch, foot, and mile; ounce, pound, and ton; pint, quart, and gallon; volt, ampere, and kilowatt hours; second ...

2012-09-08T23:59:59.000Z

73

Catalysis and Reactivity  

NLE Websites -- All DOE Office Websites (Extended Search)

understanding of basic principles of surface reactivity and its control by surface modification, on identification of active sites and full characterization of their electronic...

74

The Ampere and Electrical Standards  

Science Conference Proceedings (OSTI)

... This discovery allowed Volta to con- struct the world's first electric battery. ... cell [2]. The Weston cell consists of a cad- mium amalgam anode and a ...

2001-02-09T23:59:59.000Z

75

DESIGN AND OPERATION OF A 10.000 GPM D.C. ELECTROMAGNETIC SODIUM PUMP AND 250.000 AMPERE HOMOPOLAR GENERATOR  

SciTech Connect

single unit with the abililty to pump highly radioactive sodium (10/sup 8/ Mev/(cm/sup 3/) (sec) at high temperature (800 deg C) is described. The unit components are aligned vertically to reduce the electrical conductor length between homopolar generator and pump. The entire structure, including the 1250- hp drive motor is 30 ft high and weighs 35 tons. The pump is designed to develop a head of 75 psi at a pumping rate of 10,000 gpm. At this rate the generator must deliver 250,000 amp at 2.5 v. The low-voltage requirement of the pump permits the use of flat sheet insulation of pure mica or ceramic. The pump is limited in temperature by the curie point of iron (763 deg C). The homopolar generator is of the liquid brush type: eutectic NaK serves as the current- conductor between the rotating and stationary members. There are no windings in the machine other per strap. The essence of the pump-power supply unit lies in its ability to convert 2300-volt, 3-phase electrical power to controllable sodium pumping. Tests on the unit have revealed many interesting results which will aid greatly in the design of advanced models. (auth) Performacne tests are being conducted on two prootype 5000-gpm sodium pumps for application in the primary and secondary heat transfer systems of the EBR-II. Both pumps, one electromagnetic and one mechanical, have operated more than 5500 hr in sodium at temperatures whcih chave exceeded 800 deg F. The pump designs and test facilities are descrbied. (auth)

Jaross, R.A.; Barnes, A.H.

1958-10-31T23:59:59.000Z

76

Reactive Power Compensator.  

DOE Patents (OSTI)

A system and method for determining and providing reactive power compensation for an inductive load. A reactive power compensator (50,50') monitors the voltage and current flowing through each of three distribution lines (52a, 52b, 52c), which are supplying three-phase power to one or more inductive loads. Using signals indicative of the current on each of these lines when the voltage waveform on the line crosses zero, the reactive power compensator determines a reactive power compensator capacitance that must be connected to the lines to maintain a desired VAR level, power factor, or line voltage. Alternatively, an operator can manually select a specific capacitance for connection to each line, or the capacitance can be selected based on a time schedule. The reactive power compensator produces control signals, which are coupled through optical fibers (102/106) to a switch driver (110, 110') to select specific compensation capacitors (112) for connections to each line. The switch driver develops triggering signals that are supplied to a plurality of series-connected solid state switches (350), which control charge current in one direction in respect to ground for each compensation capacitor. During each cycle, current flows from ground to charge the capacitors as the voltage on the line begins to go negative from its positive peak value. The triggering signals are applied to gate the solid state switches into a conducting state when the potential on the lines and on the capacitors reaches a negative peak value, thereby minimizing both the potential difference and across the charge current through the switches when they begin to conduct. Any harmonic distortion on the potential and current carried by the lines is filtered out from the current and potential signals used by the reactive power compensator so that it does not affect the determination of the required reactive compensation. 26 figs.

El-Sharkawi, M.A.; Venkata, S.S.; Chen, M.; Andexler, G.; Huang, T.

1992-07-28T23:59:59.000Z

77

Reactive power compensator  

DOE Patents (OSTI)

A system and method for determining and providing reactive power compensation for an inductive load. A reactive power compensator (50,50') monitors the voltage and current flowing through each of three distribution lines (52a, 52b, 52c), which are supplying three-phase power to one or more inductive loads. Using signals indicative of the current on each of these lines when the voltage waveform on the line crosses zero, the reactive power compensator determines a reactive power compensator capacitance that must be connected to the lines to maintain a desired VAR level, power factor, or line voltage. Alternatively, an operator can manually select a specific capacitance for connection to each line, or the capacitance can be selected based on a time schedule. The reactive power compensator produces control signals, which are coupled through optical fibers (102/106) to a switch driver (110, 110') to select specific compensation capacitors (112) for connections to each line. The switch driver develops triggering signals that are supplied to a plurality of series-connected solid state switches (350), which control charge current in one direction in respect to ground for each compensation capacitor. During each cycle, current flows from ground to charge the capacitors as the voltage on the line begins to go negative from its positive peak value. The triggering signals are applied to gate the solid state switches into a conducting state when the potential on the lines and on the capacitors reaches a negative peak value, thereby minimizing both the potential difference and across the charge current through the switches when they begin to conduct. Any harmonic distortion on the potential and current carried by the lines is filtered out from the current and potential signals used by the reactive power compensator so that it does not affect the determination of the required reactive compensation.

El-Sharkawi, Mohamed A. (Renton, WA); Venkata, Subrahmanyam S. (Woodinville, WA); Chen, Mingliang (Kirkland, WA); Andexler, George (Everett, WA); Huang, Tony (Seattle, WA)

1992-01-01T23:59:59.000Z

78

Planar Vacuum Diode With Monoenergetic Electrons  

E-Print Network (OSTI)

The paper analyses volt-ampere characteristics of a planar vacuum diode with mono-energetic electrons, emitted by the cathode (an electron beam). The movement of the electron beam in the volume of the diode is described. An analytic dependence of the volt-ampere characteristics in an unlimited and limited by the field mode of the electron beam is derived.

Dimitar G. Stoyanov

2007-06-06T23:59:59.000Z

79

Oxyferryl Heme Reactivity  

NLE Websites -- All DOE Office Websites (Extended Search)

Oxyferryl Heme Reactivity Using both Radiation and Photochemical Oxyferryl Heme Reactivity Using both Radiation and Photochemical Techniques A. M. English, T. Fox, G. Tsaprailis, C. W. Fenwick, J. F. Wishart, J. T. Hazzard, and G. Tollin Adv. Chem. Ser. 254, Ch. 6, pp. 81-98 Abstract: Flash photolysis and pulse radiolysis were used to generate reductants in situ to study the electron-transfer (ET) reactivity of the FeIV=O heme centers in myoglobin and cytochrome c peroxidase. Reduction of a5RuIII groups covalently bound to surface histidines allowed intramolecular RuII --> FeIV=O ET rates to be measured. Protonation of the oxene ligand was found to be largely rate determining in myoglobin, consistent with the lack of proton donors in its heme pocket. The large distance (21-23 Ã…) between surface histidines and the heme in wild-type

80

Reactivity of Acid Generators  

NLE Websites -- All DOE Office Websites (Extended Search)

Reactivity of Acid Generators for Chemically Amplified Resists with Reactivity of Acid Generators for Chemically Amplified Resists with Low-Energy Electrons Atsuro Nakano, Takahiro Kozawa, Seiichi Tagawa, Tomasz Szreder, James F. Wishart, Toshiyuki Kai and Tsutomu Shimokawa Jpn. J. Appl. Phys., 45, L197-L200 (2006). [Find paper at the Japanese Journal of Applied Physics] Abstract: In chemically amplified resists for ionizing radiations such as electron beams and extreme ultraviolet (EUV), low-energy electrons play an important role in the pattern formation processes. The reactivity of acid generators with low-energy electrons was evaluated using solvated electrons in tetrahydrofuran, which were generated by a pulsed electron beam. The rate constants of acid generators with the solvated electrons ranged from 0.6 to 1.9 x 1011 M-1s-1

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Reactive Power Compensating System.  

DOE Patents (OSTI)

The circuit was designed for the specific application of wind-driven induction generators. It has great potential for application in any situation where a varying reactive power load is present, such as with induction motors or generators, or for transmission network compensation.

Williams, Timothy J.; El-Sharkawi, Mohamed A.; Venkata, Subrahmanyam S.

1985-01-04T23:59:59.000Z

82

Reactive power compensating system  

DOE Patents (OSTI)

The reactive power of an induction machine is compensated by providing fixed capacitors on each phase line for the minimum compensation required, sensing the current on one line at the time its voltage crosses zero to determine the actual compensation required for each phase, and selecting switched capacitors on each line to provide the balance of the compensation required.

Williams, Timothy J. (Redondo Beach, CA); El-Sharkawi, Mohamed A. (Renton, WA); Venkata, Subrahmanyam S. (Seattle, WA)

1987-01-01T23:59:59.000Z

83

Definition: Volt | Open Energy Information  

Open Energy Info (EERE)

Volta (1745-1827), who invented the voltaic pile, possibly the first chemical battery. Also Known As V References http:www.eia.govtoolsglossaryindex.cfm?idVvolt...

84

Grid Shunt Reactive Power Compensation  

Science Conference Proceedings (OSTI)

This report provides essential information on transmission grid shunt reactive power compensation, with particular focus on controllable reactive power sources such as the static var controller (SVC). Applying the information presented in this report can help electric utilities planning grid shunt reactive power compensation strategies or operating shunt reactive power compensation equipment to increase grid reliability, improve grid performance and prevent costly cascading outages. The report is intende...

2008-11-26T23:59:59.000Z

85

Reactive Air Aluminization  

DOE Green Energy (OSTI)

Ferritic stainless steels and other alloys are of great interest to SOFC developers for applications such as interconnects, cell frames, and balance of plant components. While these alloys offer significant advantages (e.g., low material and manufacturing cost, high thermal conductivity, and high temperature oxidation resistance), there are challenges which can hinder their utilization in SOFC systems; these challenges include Cr volatility and reactivity with glass seals. To overcome these challenges, protective coatings and surface treatments for the alloys are under development. In particular, aluminization of alloy surfaces offers the potential for mitigating both evaporation of Cr from the alloy surface and reaction of alloy constituents with glass seals. Commercial aluminization processes are available to SOFC developers, but they tend to be costly due to their use of exotic raw materials and/or processing conditions. As an alternative, PNNL has developed Reactive Air Aluminization (RAA), which offers a low-cost, simpler alternative to conventional aluminization methods.

Choi, Jung-Pyung; Chou, Y. S.; Stevenson, Jeffry W.

2011-10-28T23:59:59.000Z

86

Reactive Maintenance | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Reactive Maintenance Reactive Maintenance Reactive Maintenance October 7, 2013 - 9:40am Addthis Reactive maintenance follows a run-it-until-it-breaks strategy where no actions or efforts are taken to maintain equipment as intended by the manufacturer. Studies indicate this is still the predominant mode of maintenance for Federal facilities. Advantages Reactive maintenance advantages are a double-edged sword. Federal agencies following a purely reactive maintenance strategy can expect little expenditures for manpower or system upkeep until something breaks. However, systems do break. With new equipment, Federal agencies can expect minimal incidents of failure. However, older equipment often experiences higher failure incidents and costlier repairs. Other advantages of reactive maintenance are:

87

The Tasman Project Of Seafloor Magnetotelluric Exploration  

E-Print Network (OSTI)

units (for example the volt which equals 1 A- I .kg.m2.s-3).C=coulomb D E R S p (j n V=volt Q=ohm S O.m S.m- l S=siemensunits of metres (m), seconds (s), volts (V), amperes (A) and

Ferguson, Ian James

1988-01-01T23:59:59.000Z

88

Reactive rules on the web  

Science Conference Proceedings (OSTI)

Reactive rules are used for programming rule-based, reactive systems, which have the ability to detect events and respond to them automatically in a timely manner. Such systems are needed on the Web for bridging the gap between the existing, passive ...

Bruno Berstel; Philippe Bonnard; François Bry; Michael Eckert; Paula-Lavinia P?trânjan

2007-09-01T23:59:59.000Z

89

Federal Energy Management Program: Reactive Maintenance  

NLE Websites -- All DOE Office Websites (Extended Search)

Reactive Reactive Maintenance to someone by E-mail Share Federal Energy Management Program: Reactive Maintenance on Facebook Tweet about Federal Energy Management Program: Reactive Maintenance on Twitter Bookmark Federal Energy Management Program: Reactive Maintenance on Google Bookmark Federal Energy Management Program: Reactive Maintenance on Delicious Rank Federal Energy Management Program: Reactive Maintenance on Digg Find More places to share Federal Energy Management Program: Reactive Maintenance on AddThis.com... Sustainable Buildings & Campuses Operations & Maintenance Federal Requirements Program Management Commissioning Metering Computerized Maintenance Management Systems Maintenance Types Reactive Preventive Predictive Reliability-Centered Major Equipment Types

90

Reactivity of heat treated chars  

DOE Green Energy (OSTI)

Reactivities of a number of chars produced from American coals varying in rank from lignite to anthracite have been measured in air, CO/sub 2/, steam and H/sub 2/. The variables chosen for the study were: rank of the parent coal, inorganic matter content, particle size, reaction temperature and pressure as well as heat treatment conditions used during char preparation. In all gasification atmospheres studied, reactivity plots for different chars are essentially of the same general shape and have three distinct regions. The reaction rate first increases slowly with time. The plot then goes through a maximum in slope, followed by a lengthy region of decreasing slope as burn-off approaches 100 percent. The shape of the burn-off curves can be explained on the basis of what is known about the development of porosity and surface area in microporous chars as they undergo gasification. Using an adjustable time parameter, equations have been developed which successfully correlate the reactivity data. Char reactivity decreases, in general, with increase in rank of the parent coal. Reactivities of chars in air, CO/sub 2/ and steam increase over 150-fold in going from a low volatile bituminous to a lignite parent coal; the spread in char reactivities in H/sub 2/ is only 30-fold. Removal of inorganic matter from coal precursors prior to their charring or from chars produced from the raw coals has a marked effect on char reactivity and surface area. Removal of inorganic matter (by acid washing) decreases, in general, reactivity of chars produced from lower rank coals, whereas reactivities of chars derived from higher rank coals increase.

Mahajan, O. P.; Walker, Jr., P. L.

1977-01-01T23:59:59.000Z

91

DETERMINATION OF SPECIFIC NEUTRONIC REACTIVITY  

DOE Patents (OSTI)

A method is given for production-line determination of the specific neutronic reactivity of such objects as individual nuclear fuel or neutron absorber elements and is notable for rapidity and apparatus simplicity. The object is incorporated in a slightly sub-critical chain fission reactive assembly having a discrete neutron source, thereby establishing a K/sub eff/ within the crucial range of 0.95 to 0.995. The range was found to afford, uniquely, flux- transient damped response in a niatter of seconds simultaneously with acceptable analytical sensitivity. The resulting neutron flux measured at a situs spaced from both object and source within the assembly serves as a calibrable indication of said reactivity.

Dessauer, G.

1960-05-10T23:59:59.000Z

92

Treating water-reactive wastes  

DOE Green Energy (OSTI)

Some compounds and elements, such as lithium hydride, magnesium, sodium, and calcium react violently with water to generate much heat and produce hydrogen. The hydrogen can ignite or even form an explosive mixture with air. Other metals may react rapidly only if they are finely divided. Some of the waste produced at Los Alamos National Laboratory includes these metals that are contaminated with radioactivity. By far the greatest volume of water-reactive waste is lithium hydride contaminated with depleted uranium. Reactivity of the water-reactive wastes is neutralized with an atmosphere of humid nitrogen, which prevents the formation of an explosive mixture of hydrogen and air. When we adjust the temperature of the nitrogen and the humidifier, the nitrogen can be more or less humid, and the rate of reaction can be adjusted and controlled. Los Alamos has investigated the rates of reaction of lithium hydride as a function of the temperature and humidity, and, as anticipated, they in with in temperature and humidity. Los Alamos will investigate other variables. For example, the nitrogen flow will be optimized to conserve nitrogen and yet keep the reaction rates high. Reaction rates will be determined for various forms of lithium waste, from small chips to powder. Bench work will lead to the design of a skid-mounted process for treating wastes. Other water-reactive wastes will also be investigated.

Lussiez, G.W.

1993-01-01T23:59:59.000Z

93

Treating water-reactive wastes  

DOE Green Energy (OSTI)

Some compounds and elements, such as lithium hydride, magnesium, sodium, and calcium react violently with water to generate much heat and produce hydrogen. The hydrogen can ignite or even form an explosive mixture with air. Other metals may react rapidly only if they are finely divided. Some of the waste produced at Los Alamos National Laboratory includes these metals that are contaminated with radioactivity. By far the greatest volume of water-reactive waste is lithium hydride contaminated with depleted uranium. Reactivity of the water-reactive wastes is neutralized with an atmosphere of humid nitrogen, which prevents the formation of an explosive mixture of hydrogen and air. When we adjust the temperature of the nitrogen and the humidifier, the nitrogen can be more or less humid, and the rate of reaction can be adjusted and controlled. Los Alamos has investigated the rates of reaction of lithium hydride as a function of the temperature and humidity, and, as anticipated, they in with in temperature and humidity. Los Alamos will investigate other variables. For example, the nitrogen flow will be optimized to conserve nitrogen and yet keep the reaction rates high. Reaction rates will be determined for various forms of lithium waste, from small chips to powder. Bench work will lead to the design of a skid-mounted process for treating wastes. Other water-reactive wastes will also be investigated.

Lussiez, G.W.

1993-05-01T23:59:59.000Z

94

Particle Swarm Optimization Based Reactive Power Optimization  

E-Print Network (OSTI)

Reactive power plays an important role in supporting the real power transfer by maintaining voltage stability and system reliability. It is a critical element for a transmission operator to ensure the reliability of an electric system while minimizing the cost associated with it. The traditional objectives of reactive power dispatch are focused on the technical side of reactive support such as minimization of transmission losses. Reactive power cost compensation to a generator is based on the incurred cost of its reactive power contribution less the cost of its obligation to support the active power delivery. In this paper an efficient Particle Swarm Optimization (PSO) based reactive power optimization approach is presented. The optimal reactive power dispatch problem is a nonlinear optimization problem with several constraints. The objective of the proposed PSO is to minimize the total support cost from generators and reactive compensators. It is achieved by maintaining the whole system power loss as minimum...

Sujin, P R; Linda, M Mary

2010-01-01T23:59:59.000Z

95

Engine combustion control via fuel reactivity stratification  

Science Conference Proceedings (OSTI)

A compression ignition engine uses two or more fuel charges having two or more reactivities to control the timing and duration of combustion. In a preferred implementation, a lower-reactivity fuel charge is injected or otherwise introduced into the combustion chamber, preferably sufficiently early that it becomes at least substantially homogeneously dispersed within the chamber before a subsequent injection is made. One or more subsequent injections of higher-reactivity fuel charges are then made, and these preferably distribute the higher-reactivity matter within the lower-reactivity chamber space such that combustion begins in the higher-reactivity regions, and with the lower-reactivity regions following thereafter. By appropriately choose the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot).

Reitz, Rolf Deneys; Hanson, Reed M; Splitter, Derek A; Kokjohn, Sage L

2013-12-31T23:59:59.000Z

96

Reactive and Catalytic Air Purification Materials - Energy ...  

Biomass and Biofuels; Building Energy Efficiency; Electricity Transmission; ... Target selectivity can be controlled through selection of reactive components.

97

Directional Reactive Power Ground Plane Transmission  

Directional Reactive Power Ground Plane Transmission Technology Summary ... The invention can transmit electrical power through the surface of the ...

98

Partnering Today: Technology Transfer Highlights Reactive ...  

THE LLNL TECHNOLOGY COMPANY PRODUCT Partnering Today: Technology Transfer Highlights Reactive NanoTechnologies Inc.: Temperature-controlled Precision Bonding

99

Gamma Survey of a Permeable Reactive Barrier at Monticello, Utah...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Gamma Survey of a Permeable Reactive Barrier at Monticello, Utah Gamma Survey of a Permeable Reactive Barrier at Monticello, Utah Gamma Survey of a Permeable Reactive Barrier at...

100

Permeable Reactive Barriers | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Permeable Reactive Barriers Permeable Reactive Barriers Permeable Reactive Barriers Permeable Reactive Barrier Field Projects Durango, Colorado DOE installed a PRB in October 1995 to treat ground water from a uranium mill tailings disposal site at Durango, Colorado Read more Cañon City, Colorado ESL personnel conduct tests and help evaluate performance at other PRB sites, such as Cotter Corporation's Cañon City site in Colorado. Read more Monticello, Utah Installation of a PRB hydraulically downgradient of the Monticello, Utah, millsite was completed June 30, 1999, as an Interim Remedial Action. Read more A permeable reactive barrier (PRB) is a zone of reactive material placed underground to intercept and react with a contaminant plume in ground water. Typically, PRBs are emplaced by replacing soils with reactive

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

HelioVolt Business Plan Pitch  

Science Conference Proceedings (OSTI)

... Showa Shell and Shell Solar successfully scaled up this process to ... Page 9. 9 Role of Micro and Nanostructuring in CIGS PV Device Operation ...

2012-10-04T23:59:59.000Z

102

EV Project Chevrolet Volt Vehicle Summary Report  

NLE Websites -- All DOE Office Websites (Extended Search)

124,954 21,973 7,718 Percent of all charging events 81% 14% 5% Electric Vehicle Mode (EV) Operation Gasoline fuel economy (mpg) No Fuel Used AC electrical energy consumption (AC...

103

Benchmarks for Quantifying Fuel Reactivity Depletion Uncertainty  

Science Conference Proceedings (OSTI)

Analytical methods, described in this report, are used to systematically determine experimental fuel sub-batch reactivities as a function of burnup. Fuel sub-batch reactivities are inferred using more than 600 in-core pressurized water reactor (PWR) flux maps taken during 44 cycles of operation at the Catawba and McGuire nuclear power plants. The analytical methods systematically search for fuel sub-batch reactivities that minimize differences between measured and computed reaction rates, using Studsvik ...

2011-08-08T23:59:59.000Z

104

Rejuvenating Permeable Reactive Barriers by Chemical Flushing  

Energy.gov (U.S. Department of Energy (DOE))

Final Report:Rejuvenating Permeable Reactive Barriers by Chemical Flushing,U.S. Environmental Protection Agency, Region 8 Support.August 2004

105

ENGINE COMBUSTION CONTROL VIA FUEL REACTIVITY ...  

A compression ignition engine uses two or more fuel charges having two or more reactivities to control the timing and duration of combustion. In a ...

106

Electrochemistry of Enargite: Reactivity in Alkaline Solutions  

Science Conference Proceedings (OSTI)

The reactivity of enargite samples from Montana, US and Quiruvilca, Peru were studied under alkaline conditions, pH range of 8-13, using a cyclic voltammetry ...

107

Reactive Air Aluminizing - Energy Innovation Portal  

Reactive Air Aluminizing is a process for applying a protective coating on steel components in solid oxide fuel ... Building Energy Efficiency; ...

108

Reactive Air Aluminizing - Energy Innovation Portal  

Reactive Air Aluminizing is a process for applying a protective coating on steel components in solid oxide fuel cells and other high temperature electrochemical devices.

109

Definition: Automated Capacitors | Open Energy Information  

Open Energy Info (EERE)

Capacitors Capacitors Jump to: navigation, search Dictionary.png Automated Capacitors Capacitors can increase the voltage on a distribution circuit by providing reactive power (often referred to as volt-amperes-reactive or VArs). Capacitor banks are switched in discrete steps, either manually, or in response to the voltage at the location where they are connected; typically, distribution capacitor banks are switched in a single step. If the voltage falls too far below the set point, the capacitor is switched in to raise the voltage. If the voltage rises too high above the set point, the capacitor is switched out to lower the voltage. Automated capacitors can be switched in coordination with other voltage control devices with signals from local sensors, distribution automation systems, or grid

110

Proceedings: Fossil Plant Layup and Reactivation Conference  

Science Conference Proceedings (OSTI)

In recent years, the layup and reactivation of fossil-fired power plants has become more important as increasing numbers of utilities develop a need for retaining capacity not currently needed. A 1992 EPRI conference highlighted key technical issues, focusing on proven layup procedures, descriptions of layup equipment and preservation methods, layup and reactivation case studies, and summaries of regulatory issues.

1992-10-01T23:59:59.000Z

111

Simulations of highly reactive fluids  

SciTech Connect

We report density functional molecular dynamics simulations to determine the early chemical events of hot (T = 3000 K) and dense (1.97 g/cm{sup 3}, V/V{sub 0} = 0.68) nitromethane (CH{sub 3}NO{sub 2}). The first step in the decomposition process is an intermolecular proton abstraction mechanism that leads to the formation of CH{sub 3}NO{sub 2}H and the aci ion H{sub 2}CNO{sub 2}{sup -}, in support of evidence from static high-pressure and shock experiments. An intramolecular hydrogen transfer that transforms nitromethane into the aci acid form, CH{sub 2}NO{sub 2}H, accompanies this event. This is the first confirmation of chemical reactivity with bond selectivity for an energetic material near the condition of fully reacted specimen. We also report the decomposition mechanism followed up to the formation of H{sub 2}O as the first stable product.

Fried, L E; Manaa, M R; Reed, E J

2005-07-21T23:59:59.000Z

112

Reactive Power Measurement Using the Wavelet Transform  

E-Print Network (OSTI)

Abstract—This paper provides the theoretical basis for the measurement of reactive and distortion powers from the wavelet transforms. The measurement of reactive power relies on the use of broad-band phase-shift networks to create concurrent in-phase currents and quadrature voltages. The wavelet real power computation resulting from these 90 phase-shift networks yields the reactive power associated with each wavelet frequency level or subband. The distortion power at each wavelet subband is then derived from the real, reactive and apparent powers of the subband, where the apparent power is the product of the v; i element pair's subband rms voltage and current. The advantage of viewing the real and reactive powers in the wavelet domain is that the domain preserves both the frequency and time relationship of these powers. In addition, the reactive power associated with each wavelet subband is a signed quantity and thus has a direction associated with it. This permits tracking the reactive power flow in each subband through the power system. Index Terms—Digital signal processing, phase shift networks, measurement, power, RMS, subband, wavelets. I.

Weon-ki Yoon; Michael J. Devaney

2000-01-01T23:59:59.000Z

113

Comparison of biomass and coal char reactivities  

SciTech Connect

Char combustion is typically the rate limiting step during the combustion of solid fuels. The magnitude and variation of char reactivity during combustion are, therefore, of primary concern when comparing solid fuels such as coal and biomass. In an effort to evaluate biomass` potential as a sustainable and renewable energy source, the reactivities of both biomass and coal chars were compared using Sandia`s Captive Particle Imaging (CPI) apparatus. This paper summarizes the experimental approach used to determine biomass and coal reactivities and presents results from CPT experiments. The reactivity of six types of char particles, two high-rank coal chars, two low-rank coal chars, and two biomass chars, were investigated using the CPT apparatus. Results indicate that both of the high-rank coal chars have relatively low reactivities when compared with the higher reactivities measured for the low-rank coal and the biomass chars. In addition, extinction behavior of the chars support related investigations that suggest carbonaceous structural ordering is an important consideration in understanding particle reactivity as a function of extent of burnout. High-rank coal chars were found to have highly ordered carbon structures, where as, both low-rank coal and biomass chars were found to have highly disordered carbon structures.

Huey, S.P. [Sandia National Labs., Livermore, CA (United States); Davis, K.A. [Reaction Engineering International, Salt Lake City, UT (United States); Hurt, R.H. [Brown Univ., Providence, RI (United States). Div. of Engineering

1995-08-01T23:59:59.000Z

114

Systematic approach for chemical reactivity evaluation  

E-Print Network (OSTI)

Under certain conditions, reactive chemicals may proceed into uncontrolled chemical reaction pathways with rapid and significant increases in temperature, pressure, and/or gas evolution. Reactive chemicals have been involved in many industrial incidents, and have harmed people, property, and the environment. Evaluation of reactive chemical hazards is critical to design and operate safer chemical plant processes. Much effort is needed for experimental techniques, mainly calorimetric analysis, to measure thermal reactivity of chemical systems. Studying all the various reaction pathways experimentally however is very expensive and time consuming. Therefore, it is essential to employ simplified screening tools and other methods to reduce the number of experiments and to identify the most energetic pathways. A systematic approach is presented for the evaluation of reactive chemical hazards. This approach is based on a combination of computational methods, correlations, and experimental thermal analysis techniques. The presented approach will help to focus the experimental work to the most hazardous reaction scenarios with a better understanding of the reactive system chemistry. Computational methods are used to predict reaction stoichiometries, thermodynamics, and kinetics, which then are used to exclude thermodynamically infeasible and non-hazardous reaction pathways. Computational methods included: (1) molecular group contribution methods, (2) computational quantum chemistry methods, and (3) correlations based on thermodynamic-energy relationships. The experimental techniques are used to evaluate the most energetic systems for more accurate thermodynamic and kinetics parameters, or to replace inadequate numerical methods. The Reactive System Screening Tool (RSST) and the Automatic Pressure Tracking Adiabatic Calorimeter (APTAC) were employed to evaluate the reactive systems experimentally. The RSST detected exothermic behavior and measured the overall liberated energy. The APTAC simulated near-adiabatic runaway scenarios for more accurate thermodynamic and kinetic parameters. The validity of this approach was investigated through the evaluation of potentially hazardous reactive systems, including decomposition of di-tert-butyl peroxide, copolymerization of styrene-acrylonitrile, and polymerization of 1,3-butadiene.

Aldeeb, Abdulrehman Ahmed

2003-12-01T23:59:59.000Z

115

Theoretical and Experimental Evaluation of Chemical Reactivity  

E-Print Network (OSTI)

Reactive chemicals are presented widely in the chemical and petrochemical process industry. Their chemical reactivity hazards have posed a significant challenge to the industries of manufacturing, storage and transportation. The accidents due to reactive chemicals have caused tremendous loss of properties and lives, and damages to the environment. In this research, three classes of reactive chemicals (unsaturated hydrocarbons, self-reacting chemicals, energetic materials) were evaluated through theoretical and experimental methods. Methylcyclopentadiene (MCP) and Hydroxylamine (HA) are selected as representatives of unsaturated hydrocarbons and self-reacting chemicals, respectively. Chemical reactivity of MCP, including isomerization, dimerization, and oxidation, is investigated by computational chemistry methods and empirical thermodynamic–energy correlation. Density functional and ab initio methods are used to search the initial thermal decomposition steps of HA, including unimolecular and bimolecular pathways. In addition, solvent effects are also examined using water cluster methods and Polarizable Continuum Models (PCM) for aqueous solution of HA. The thermal stability of a basic energetic material, Nitroethane, is investigated through both theoretical and experimental methods. Density functional methods are employed to explore the initial decomposition pathways, followed by developing detailed reaction networks. Experiments with a batch reactor and in situ GC are designed to analyze the distribution of reaction products and verify reaction mechanisms. Overall kinetic model is also built from calorimetric experiments using an Automated Pressure Tracking Adiabatic Calorimeter (APTAC). Finally, a general evaluation approach is developed for a wide range of reactive chemicals. An index of thermal risk is proposed as a preliminary risk assessment to screen reactive chemicals. Correlations are also developed between reactivity parameters, such as onset temperature, activation energy, and adiabatic time to maximum rate based on a limited number, 37 sets, of Differential Scanning Calorimeter (DSC) data. The research shows broad applications in developing reaction mechanisms at the molecular level. The methodology of reaction modeling in combination with molecular modeling can also be used to study other reactive chemical systems.

Wang, Qingsheng

2010-08-01T23:59:59.000Z

116

COAL SLAGGING AND REACTIVITY TESTING  

SciTech Connect

Union Fenosa's La Robla I Power Station is a 270-MW Foster Wheeler arch-fired system. The unit is located at the mine that provides a portion of the semianthracitic coal. The remaining coals used are from South Africa, Russia, Australia, and China. The challenges at the La Robla I Station stem from the various fuels used, the characteristics of which differ from the design coal. The University of North Dakota Energy & Environmental Research Center (EERC) and the Lehigh University Energy Research Center (LUERC) undertook a program to assess problematic slagging and unburned carbon issues occurring at the plant. Full-scale combustion tests were performed under baseline conditions, with elevated oxygen level and with redistribution of air during a site visit at the plant. During these tests, operating information, observations and temperature measurements, and coal, slag deposit, and fly ash samples were obtained to assess slagging and unburned carbon. The slagging in almost all cases appeared due to elevated temperatures rather than fuel chemistry. The most severe slagging occurred when the temperature at the sampling port was in excess of 1500 C, with problematic slagging where first-observed temperatures exceeded 1350 C. The presence of anorthite crystals in the bulk of the deposits analyzed indicates that the temperatures were in excess of 1350 C, consistent with temperature measurements during the sampling period. Elevated temperatures and ''hot spots'' are probably the result of poor mill performance, and a poor distribution of the coal from the mills to the specific burners causes elevated temperatures in the regions where the slag samples were extracted. A contributing cause appeared to be poor combustion air mixing and heating, resulting in oxygen stratification and increased temperatures in certain areas. Air preheater plugging was observed and reduces the temperature of the air in the windbox, which leads to poor combustion conditions, resulting in unburned carbon as well as slagging. A second phase of the project involved advanced analysis of the baseline coal along with an Australian coal fired at the plant. These analysis results were used in equilibrium thermodynamic modeling along with a coal quality model developed by the EERC to assess slagging, fouling, and opacity for the coals. Bench-scale carbon conversion testing was performed in a drop-tube furnace to assess the reactivity of the coals. The Australian coal had a higher mineral content with significantly more clay minerals present than the baseline coal. The presence of these clay minerals, which tend to melt at relatively low temperatures, indicated a higher potential for problematic slagging than the baseline coal. However, the pyritic minerals, comprising over 25% of the baseline mineral content, may form sticky iron sulfides, leading to severe slagging in the burner region if local areas with reducing conditions exist. Modeling results indicated that neither would present significant fouling problems. The Australian coal was expected to show slagging behavior much more severe than the baseline coal except at very high furnace temperatures. However, the baseline coal was predicted to exhibit opacity problems, as well as have a higher potential for problematic calcium sulfate-based low-temperature fouling. The baseline coal had a somewhat higher reactivity than the Australian coal, which was consistent with both the lower average activation energy for the baseline coal and the greater carbon conversion at a given temperature and residence time. The activation energy of the baseline coal showed some effect of oxygen on the activation energy, with E{sub a} increasing at the lower oxygen concentration, but may be due to the scatter in the baseline coal kinetic values at the higher oxygen level tested.

Donald P. McCollor; Kurt E. Eylands; Jason D. Laumb

2003-10-01T23:59:59.000Z

117

Final Report Phase II: Performance Evaluation of Permeable Reactive  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Final Report Phase II: Performance Evaluation of Permeable Reactive Final Report Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing Final Report Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing Final Report Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing Final Report Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing More Documents & Publications Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing Rejuvenating Permeable Reactive Barriers by Chemical Flushing Final Report - Rejuvenating Permeable Reactive Barriers by Chemical

118

Hydraulic Conductivity of the Monticello Permeable Reactive Barrier  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Hydraulic Conductivity of the Monticello Permeable Reactive Barrier Hydraulic Conductivity of the Monticello Permeable Reactive Barrier November 2005 Update Hydraulic Conductivity of the Monticello Permeable Reactive Barrier November 2005 Update Hydraulic Conductivity of the Monticello Permeable Reactive Barrier November 2005 Update Hydraulic Conductivity of the Monticello Permeable Reactive Barrier November 2005 Update More Documents & Publications Variation in Hydraulic Conductivity Over Time at the Monticello Permeable Reactive Barrier Performance Assessment and Recommendations for Rejuvenation of a Permeable Reactive Barrier: Cotter Corporation's Cañon City, Colorado, Uranium Mill Performance Assessment and Recommendations for Rejuvenation of a Permeable Reactive Barrier: Cotter Corporation's Cañon City, Colorado, Uranium

119

Efficient and Reliable Reactive Power Supply and Consumption...  

NLE Websites -- All DOE Office Websites (Extended Search)

Efficient and Reliable Reactive Power Supply and Consumption - Insights from an Integrated Program of Engineering and Economics Research Title Efficient and Reliable Reactive Power...

120

Olefin production via reactive distillation based Olefin metathesis.  

E-Print Network (OSTI)

??Reactive distillation is a combination of a traditional multi-stage distillation column with a chemical reaction. The primary benefits of a reactive distillation process are reduced… (more)

Morrison, Ryan Frederick

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

A Parametric Reactive Distillation Study: Economic Feasibility and Design Heuristics.  

E-Print Network (OSTI)

??The integration of reaction and distillation into a single column is called reactive distillation or catalytic distillation. Reactive distillation provides many benefits such as reduced… (more)

Hoyme, Craig Alan

2004-01-01T23:59:59.000Z

122

Observations on the Coke Air Reactivity Test - Programmaster.org  

Science Conference Proceedings (OSTI)

Coke air reactivities are strongly dependent on coke calcination levels and it is possible to drive air reactivities lower by increasing calcining temperatures.

123

Reactivity control assembly for nuclear reactor  

DOE Patents (OSTI)

Reactivity control assembly for nuclear reactor comprises supports stacked above reactor core for holding control rods. Couplers associated with the supports and a vertically movable drive shaft have lugs at their lower ends for engagement with the supports.

Bollinger, Lawrence R. (Schenectady, NY)

1984-01-01T23:59:59.000Z

124

A Tariff for Reactive Power - IEEE  

DOE Green Energy (OSTI)

This paper describes a suggested tariff or payment for the local supply of reactive power from distributed energy resources. The authors consider four sample customers, and estimate the cost of supply of reactive power for each customer. The power system savings from the local supply of reactive power are also estimated for a hypothetical circuit. It is found that reactive power for local voltage regulation could be supplied to the distribution system economically by customers when new inverters are installed. The inverter would be supplied with a power factor of 0.8, and would be capable of local voltage regulation to a schedule supplied by the utility. Inverters are now installed with photovoltaic systems, fuel cells and microturbines, and adjustable-speed motor drives.

Kueck, John D [ORNL; Tufon, Christopher [Pacific Gas and Electric Company; Isemonger, Alan [California Independent System Operator; Kirby, Brendan J [ORNL

2008-11-01T23:59:59.000Z

125

Mild coal pretreatment to improve liquefaction reactivity  

SciTech Connect

This report describes work completed during the fourth quarter of a three year project to study the effects of mild chemical pretreatment on coal dissolution reactivity during low severity liquefaction or coal/oil coprocessing. The overall objective of this research is to elucidate changes in the chemical and physical structure of coal by pretreating with methanol or other simple organic solvent and a trace amount of hydrochloric acid and measure the influence of these changes on coal dissolution reactivity. This work is part of a larger effort to develop a new coal liquefaction or coal/oil coprocessing scheme consisting of three main process steps: (1) mile pretreatment of the feed coal to enhance dissolution reactivity and dry the coal, (2) low severity thermal dissolution of the pretreated coal to obtain a very reactive coal-derived residual material amenable to upgrading, and (3) catalytic upgrading of the residual products to distillate liquids.

Miller, R.L.

1991-01-01T23:59:59.000Z

126

Groundwater well with reactive filter pack  

DOE Patents (OSTI)

A method and apparatus for the remediation of contaminated soil and ground water wherein a reactive pack material is added to the annular fill material utilized in standard well construction techniques.

Gilmore, Tyler J. (Pasco, WA); Holdren, Jr., George R. (Kennewick, WA); Kaplan, Daniel I. (Richland, WA)

1998-01-01T23:59:59.000Z

127

Fossil plant layup and reactivation conference: Proceedings  

Science Conference Proceedings (OSTI)

The Fossil Plant Layup and Reactivation Conference was held in New Orleans, Louisiana on April 14--15, 1992. The Conference was sponsored by EPRI and hosted by Entergy Services, Inc. to bring together representatives from utilities, consulting firms, manufacturers and architectural engineers. Eighteen papers were presented in three sessions. These sessions were devoted to layup procedures and practices, and reactivation case studies. A panel discussion was held on the second day to interactively discuss layup and reactivation issues. More than 80 people attended the Conference. This report contains technical papers and a summary of the panel discussion. Of the eighteen papers, three are related to general, one is related to regulatory issues, three are related to specific equipment, four are related to layup procedures and practices, and seven are layup and reactivation case studies.

Not Available

1992-10-01T23:59:59.000Z

128

Oxidation Resistance of Reactive Atoms in Graphene  

SciTech Connect

We have found that reactive elements that are normally oxidized at room temperature are present as individual atoms or clusters on and in graphene. Oxygen is present in these samples but it is only detected in the thicker amorphous carbon layers present in the graphene specimens we have examined. However, we have seen no evidence that oxygen reacts with the impurity atoms and small clusters of these normally reactive elements when they are incorporated in the graphene layers. First principles calculations suggest that the oxidation resistance is due to kinetic effects such as preferential bonding of oxygen to nonincorporated atoms and H passivation. The observed oxidation resistance of reactive atoms in graphene may allow the use of these incorporated metals in catalytic applications. It also opens the possibility of designing and producing electronic, opto-electronic, and magnetic devices based on these normally reactive atoms.

Chisholm, Matthew F [ORNL; Duscher, Gerd [University of Tennessee, Knoxville (UTK); Windl, Wolfgang [Ohio State University

2012-01-01T23:59:59.000Z

129

Radiative Forcing Due to Reactive Gas Emissions  

Science Conference Proceedings (OSTI)

Reactive gas emissions (CO, NOx, VOC) have indirect radiative forcing effects through their influences on tropospheric ozone and on the lifetimes of methane and hydrogenated halocarbons. These effects are quantified here for the full set of ...

T. M. L. Wigley; S. J. Smith; M. J. Prather

2002-09-01T23:59:59.000Z

130

Enhanced Oxidative Reactivity for Anthracite Coal via a Reactive Ball Milling Pretreatment Step  

Science Conference Proceedings (OSTI)

Reactive ball milling in a cyclohexene solvent significantly increases the oxidative reactivity of an anthracite coal, due to the combined effects of particle size reduction, metal introduction, introduction of volatile matter, and changes in carbon structure. Metals introduced during milling can be easily removed via a subsequent demineralization process, and the increased reactivity is retained. Solvent addition alters the morphological changes that occur during pyrolysis and leads to a char with significantly increased reactivity. When the solvent is omitted, similar effects are seen for the milled product, but a significant fraction of the char is resistant to oxidation. 33 refs., 3 figs., 1 tab.

Angela D. Lueking; Apurba Sakti; Dania Alvarez-Fonseca; Nichole Wonderling [Pennsylvania State University, PA (United States). Department of Energy and Mineral Engineering

2009-09-15T23:59:59.000Z

131

review of extraction, processing, properties & applications of reactive ...  

Science Conference Proceedings (OSTI)

REVIEW OF EXTRACTION,. PROCESSING, PROPERTIES. & APPLICATIONS OF. REACTIVE METALS. Edited by. Brajendra Mishra ...

132

Final Report Phase II: Performance Evaluation of Permeable Reactive  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Final Report Phase II: Performance Evaluation of Permeable Reactive Final Report Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing Final Report Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing Final Report Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing Final Report Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing More Documents & Publications Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing Final Report - Rejuvenating Permeable Reactive Barriers by Chemical Flushing, U.S. Environmental Protection Agency Region 8 Support

133

Phase II: Performance Evaluation of Permeable Reactive Barriers and  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Phase II: Performance Evaluation of Permeable Reactive Barriers and Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing Final Report Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing U. S. Environmental Protection Agency Region 8 Support January 2004 Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing More Documents & Publications Final Report Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing Rejuvenating Permeable Reactive Barriers by Chemical Flushing

134

Hydraulic Conductivity of the Monticello Permeable Reactive Barrier  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Hydraulic Conductivity of the Monticello Permeable Reactive Barrier Hydraulic Conductivity of the Monticello Permeable Reactive Barrier November 2005 Update Hydraulic Conductivity of the Monticello Permeable Reactive Barrier November 2005 Update Hydraulic Conductivity of the Monticello Permeable Reactive Barrier November 2005 Update Hydraulic Conductivity of the Monticello Permeable Reactive Barrier November 2005 Update More Documents & Publications Variation in Hydraulic Conductivity Over Time at the Monticello Permeable Reactive Barrier Ground-Water Table and Chemical Changes in an Alluvial Aquifer During Sustained Pumping at the Monticello, Utah, Zero-Valent Iron Treatment Cells Performance Assessment and Recommendations for Rejuvenation of a Permeable Reactive Barrier: Cotter Corporation's Cañon City, Colorado, Uranium

135

Transport Modeling of Reactive and Non-Reactive Constituents from Summitville,  

E-Print Network (OSTI)

Survey (USGS) began water- quality investigations at Summitville, Terrace #12;Figure 2. Aerial photographTransport Modeling of Reactive and Non- Reactive Constituents from Summitville, Colorado in the Wightman Fork/Alamosa River system downstream of the Summitville Mine, south-central Colorado, were

136

Reports on Initial Results of Smart Grid Investment Grant Projects  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Reports on Initial Results of Smart Grid Investment Grant Projects Reports on Initial Results of Smart Grid Investment Grant Projects (December 2012) Reports on Initial Results of Smart Grid Investment Grant Projects (December 2012) DOE is implementing the Smart Grid Investment Grant (SGIG) program under the American Recovery and Reinvestment Act of 2009. The SGIG program involves 99 projects that are deploying smart grid technologies, tools, and techniques for electric transmission, distribution, advanced metering, and customer systems. These reports present information about the devices and systems being implemented, deployment progress, expected benefits, and initial results for projects improving electric distribution system reliability; implementing advanced metering, customer systems, and time-based rates; adding advanced voltage and volt-ampere reactive (VAR) optimization (VVO)

137

STATEMENT OF CONSIDERATIONS REQUEST BY SOUTHERN COMPANY SERVICES, INC. FOR AN ADVANCE WAIVER  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

SOUTHERN COMPANY SERVICES, INC. FOR AN ADVANCE WAIVER SOUTHERN COMPANY SERVICES, INC. FOR AN ADVANCE WAIVER OF DOMESTIC AND FOREIGN PATENT RIGHTS UNDER DOE COOPERATIVE AGREEMENT NO. DE-FC02-05CH11327 ENTITLED "DEVELOPMENT OF THE UPGRADE OF THE GENERATOR VOLT AMPERE REACTIVE RESERVE (GENVARR) SYSTEM;" W(A)-05-051; CH-1338 As set out in the attached waiver petition and in subsequent discussions with DOE Patent Counsel, Southern Company Service, Inc. has requested an advance waiver of domestic and foreign patent rights for all subject inventions made under the above-identified cooperative agreement by its employees and its subawardees' employees, regardless of tier, except inventions made by subawardees eligible to retain title to inventions pursuant to P.L. 96-517, as amended, and National Laboratories.

138

Nuclear engine flow reactivity shim control  

DOE Patents (OSTI)

A nuclear engine control system is provided which automatically compensates for reactor reactivity uncertainties at the start of life and reactivity losses due to core corrosion during the reactor life in gas-cooled reactors. The coolant gas flow is varied automatically by means of specially provided control apparatus so that the reactor control drums maintain a predetermined steady state position throughout the reactor life. This permits the reactor to be designed for a constant drum position and results in a desirable, relatively flat temperature profile across the core. (Official Gazette)

Walsh, J.M.

1973-12-11T23:59:59.000Z

139

Neutron Radiography Reactor Reactivity -- Focused Lessons Learned  

SciTech Connect

As part of the Global Threat Reduction Initiative, the Neutron Radiography Reactor (NRAD) at the Idaho National Laboratory (INL) was converted from using highly enriched uranium (HEU) to low enriched uranium (LEU) fuel. After the conversion, NRAD resumed operations and is meeting operational requirements. Radiography image quality and the number of images that can be produced in a given time frame match pre-conversion capabilities. However, following the conversion, NRAD’s excess reactivity with the LEU fuel was less than it had been with the HEU fuel. Although some differences between model predictions and actual performance are to be expected, the lack of flexibility in NRAD’s safety documentation prevented adjusting the reactivity by adding more fuel, until the safety documentation could be modified. To aid future reactor conversions, a reactivity-focused Lessons Learned meeting was held. This report summarizes the findings of the lessons learned meeting and addresses specific questions posed by DOE regarding NRAD’s conversion and reactivity.

Eric Woolstenhulme; Randal Damiana; Kenneth Schreck; Ann Marie Phillips; Dana Hewit

2010-11-01T23:59:59.000Z

140

LES algorithm for turbulent reactive flows simulation  

Science Conference Proceedings (OSTI)

The paper presents the development and implementation of a Large Eddy Simulation numerical algorithm for simulating turbulent reactive flows. The numerical algorithm is based on a 5 step modified Runge - Kutta numerical scheme with a dual time stepping ... Keywords: Runge - Kutta numerical scheme, large eddy simulation, linear eddy model

Ionut Porumbel; Cristian Cârl?nescu; Florin Gabriel Florean; Constantin Eusebiu Hritcu

2010-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
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141

Acronyms, Abbreviations and Definitions, DOE Hydrogen Program FY 2010 Annual Progress Report  

NLE Websites -- All DOE Office Websites (Extended Search)

81 81 FY 2010 Annual Progress Report DOE Hydrogen Program °C Degrees Celsius °F Degrees Fahrenheit α-AlH 3 Alpha polymorph of aluminum hydride Δ Change, delta ΔG Gibbs free energy of reaction ΔH Enthalpy of reaction, enthalpy of hydrogenation ΔH° f standard heat of formation ΔK Stress intensity factor ΔP Pressure drop, pressure change ~ Approximately ≈ Equals approximately > Greater than ≥ Greater than or equal to < Less than ≤ Less than or equal to @ At # Number % Percent ® Registered trademark µA Micro ampere(s) µA/cm 2 Micro ampere(s) per square centimeter μc-Si Microcrystalline silicon µg Microgram(s) µm Micrometer(s); micron(s) µM Micromolar µmol Micromole(s) µΩ-cm 2 Micro-ohm(s)-square centimeter µV Micro volt(s)

142

Method for generating a highly reactive plasma for exhaust gas after treatment and enhanced catalyst reactivity  

DOE Patents (OSTI)

This patent application describes a method and apparatus of exhaust gas remediation that enhance the reactivity of the material catalysts found within catalytic converters of cars, trucks, and power stations.

Whealton, John H.; Hanson, Gregory R.; Storey, John M.; Raridon, Richard J.; Armfield, Jeffrey S.; Bigelow, Timothy S.; Graves, Ronald L.

2000-07-01T23:59:59.000Z

143

ENVIRONMENTAL REACTIVITY OF SOLID STATE HYDRIDE MATERIALS  

DOE Green Energy (OSTI)

In searching for high gravimetric and volumetric density hydrogen storage systems, it is inevitable that higher energy density materials will be used. In order to make safe and commercially acceptable condensed phase hydrogen storage systems, it is important to understand quantitatively the risks involved in using and handling these materials and to develop appropriate mitigation strategies to handle potential material exposure events. A crucial aspect of the development of risk identification and mitigation strategies is the development of rigorous environmental reactivity testing standards and procedures. This will allow for the identification of potential risks and implementation of risk mitigation strategies. Modified testing procedures for shipping air and/or water sensitive materials, as codified by the United Nations, have been used to evaluate two potential hydrogen storage materials, 2LiBH{sub 4} {center_dot} MgH{sub 2} and NH{sub 3}BH{sub 3}. The modified U.N. procedures include identification of self-reactive substances, pyrophoric substances, and gas-emitting substances with water contact. The results of these tests for air and water contact sensitivity will be compared to the pure material components where appropriate (e.g. LiBH{sub 4} and MgH{sub 2}). The water contact tests are divided into two scenarios dependent on the hydride to water mole ratio and heat transport characteristics. Air contact tests were run to determine whether a substance will spontaneously react with air in a packed or dispersed form. In the case of the 2LiBH{sub 4} {center_dot} MgH{sub 2} material, the results from the hydride mixture compared to the pure materials results showed the MgH{sub 2} to be the least reactive component and LiBH{sub 4} the more reactive. The combined 2LiBH{sub 4} {center_dot} MgH{sub 2} resulted in a material having environmental reactivity between these two materials. Relative to 2LiBH{sub 4} {center_dot} MgH{sub 2}, the chemical hydride NH{sub 3}BH{sub 3} was observed to be less environmentally reactive.

Gray, J; Donald Anton, D

2009-04-23T23:59:59.000Z

144

Behavior of Laminate Reactive Materials under Dynamic Loading ...  

Science Conference Proceedings (OSTI)

Presentation Title, Behavior of Laminate Reactive Materials under Dynamic Loading ... Atomistically-Informed Dislocation Dynamics Simulations of High Rate  ...

145

SIC Manufature via Reactive Infiltration - Programmaster.org  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, Materials Science & Technology 2013. Symposium, Ceramic Matrix Composites. Presentation Title, SIC Manufature via Reactive ...

146

Multiple Steady States in Azeotropic and Reactive Distillation  

E-Print Network (OSTI)

Introduction . Motivation Overview on the Contributions MSS in Reactive Distillation Conclusions Outline Multiple Steady States (MSS) Overview on the Contributions . The Starting Point . Consolidation . Industrial Applications . Incorporating Reactions MSS in Reactive Distillation Conclusions Outline Multiple Steady States (MSS) Overview on the Contributions MSS in Reactive Distillation . Prediction Method . MTBE Process Conclusions Outline Multiple Steady States (MSS) Overview on the Contributions MSS in Reactive Distillation Conclusions Distillation Overview . Ideal binary / multicomponent distillation . Homogeneous azeotropic distillation -- Heavy entrainer (extractive distillation) -- Intermediate entrainer -- "Boundary scheme" (ligh

Thomas E. Güttinger

1998-01-01T23:59:59.000Z

147

Nuclear reactivity control using laser induced polarization  

DOE Patents (OSTI)

A control element for reactivity control of a fission source provides an atomic density of .sup.3 He in a control volume which is effective to control criticality as the .sup.3 He is spin-polarized. Spin-polarization of the .sup.3 He affects the cross section of the control volume for fission neutrons and hence, the reactivity. An irradiation source is directed within the .sup.3 He for spin-polarizing the .sup.3 He. An alkali-metal vapor may be included with the .sup.3 He where a laser spin-polarizes the alkali-metal atoms which in turn, spin-couple with .sup.3 He to spin-polarize the .sup.3 He atoms.

Bowman, Charles D. (Los Alamos, NM)

1991-01-01T23:59:59.000Z

148

Nuclear reactivity control using laser induced polarization  

DOE Patents (OSTI)

A control element for reactivity control of a fission source provides an atomic density of .sup.3 He in a control volume which is effective to control criticality as the .sup.3 He is spin-polarized. Spin-polarization of the .sup.3 He affects the cross section of the control volume for fission neturons and hence, the reactivity. An irradiation source is directed within the .sup.3 He for spin-polarizing the .sup.3 He. An alkali-metal vapor may be included with the .sup.3 He where a laser spin-polarizes the alkali-metal atoms which in turn, spin-couple with .sup.3 He to spin-polarize the .sup.3 He atoms.

Bowman, Charles D. (Los Alamos, NM)

1990-01-01T23:59:59.000Z

149

Reactivity control assembly for nuclear reactor. [LMFBR  

DOE Patents (OSTI)

This invention, which resulted from a contact with the United States Department of Energy, relates to a control mechanism for a nuclear reactor and, more particularly, to an assembly for selectively shifting different numbers of reactivity modifying rods into and out of the core of a nuclear reactor. It has been proposed heretofore to control the reactivity of a breeder reactor by varying the depth of insertion of control rods (e.g., rods containing a fertile material such as ThO/sub 2/) in the core of the reactor, thereby varying the amount of neutron-thermalizing coolant and the amount of neutron-capturing material in the core. This invention relates to a mechanism which can advantageously be used in this type of reactor control system.

Bollinger, L.R.

1982-03-17T23:59:59.000Z

150

Treatment of Radioactive Reactive Mixed Waste  

Science Conference Proceedings (OSTI)

PacificEcoSolutions, Inc. (PEcoS) has installed a plasma gasification system that was recently modified and used to destroy a trimethyl-aluminum mixed waste stream from Los Alamos National Laboratory (LANL.) The unique challenge in handling reactive wastes like trimethyl-aluminum is their propensity to flame instantly on contact with air and to react violently with water. To safely address this issue, PacificEcoSolutions has developed a new feed system to ensure the safe containment of these radioactive reactive wastes during transfer to the gasification unit. The plasma gasification system safely processed the radioactively contaminated trimethyl-metal compounds into metal oxides. The waste stream came from LANL research operations, and had been in storage for seven years, pending treatment options. (authors)

Colby, S.; Turner, Z.; Utley, D. [Pacific EcoSolutions, Inc., 2025 Battelle Boulevard, Richland, Washington 99354 (United States); Duy, C. [Los Alamos National Laboratory - LA-UR-05-8410, Post Office Box 1663 MS J595, Los Alamos, New Mexico 97545 (United States)

2006-07-01T23:59:59.000Z

151

Nuclear reactivity control using laser induced polarization  

DOE Patents (OSTI)

A control element for reactivity control of a fission source provides an atomic density of {sup 3}He in a control volume which is effective to control criticality as the {sup 3}He is spin-polarized. Spin-polarization of the {sup 3}He affects the cross section of the control volume for fission neutrons and hence, the reactivity. An irradiation source is directed within the {sup 3}He for spin-polarizing the {sup 3}He. An alkali-metal vapor may be included with the {sup 3}He where a laser spin-polarizes the alkali-metal atoms which in turn, spin-couple with {sup 3}He to spin-polarize the {sup 3}He atoms. 5 figs.

Bowman, C.D.

1989-05-26T23:59:59.000Z

152

Real time reactive programming in lucid enriched with contexts  

Science Conference Proceedings (OSTI)

We present a synchronous approach to real-time reactive programming in Lucid enriched with contexts as first class objects. The declarative intensional approach allows real-time reactive programs to manipulate both events and state-based representations ... Keywords: contexts, formal verification, intensional programming, real-time reactive programming

Kaiyu Wan; Vasu Alagar; Joey Paquet

2004-09-01T23:59:59.000Z

153

RESEARCH AREA SPACE REGISTRATION USING HASP DATA ENTRY FORM Please fill in this form, using one form for each individual room.  

E-Print Network (OSTI)

600 volts Other electrical hazards Equipment Autoclave Battery Charging Area Centrifuge Chainsaw medical waste Generates universal waste Generates waste anesthetic gas Water Reactives Water Reactives

Pawlowski, Wojtek

154

Preparation of reactive beta-dicalcium silicate  

DOE Patents (OSTI)

This invention relates to the preparation of fine particles of reactive beta-dicalcium silicate by means of a solid state process which comprises firing a mixture of calcium sulfate, silica and a reducing additive selected from the group consisting of calcium sulfide, carbon, carbon monoxide, methane and hydrogen, at a temperature of about 850.degree.-1000.degree. C. A carrier gas such as nitrogen or carbon dioxide may also be added, if desired. A high concentration of sulfur dioxide is a by-product of this process.

Shen, Ming-Shing (Laramie, WY, NJ); Chen, James M. (Rahway, NJ); Yang, Ralph T. (Amherst, NY)

1982-01-01T23:59:59.000Z

155

Preparation of reactive beta-dicalcium silicate  

DOE Patents (OSTI)

This invention relates to the preparation of fine particles of reactive beta-dicalcium silicate by means of a solid state process which comprises firing a mixture of calcium sulfate, silica, and a reducing additive selected from the group consisting of calcium sulfide, carbon, carbon monoxide, methane, and hydrogen, at a temperature of about 850 to 1000/sup 0/C. A carrier gas such as nitrogen or carbon dioxide may also be added, if desired. A high concentration of sulfur dioxide is a by-product of this process.

Shen, M.S.; Chen, J.M.; Yang, R.T.

1980-02-28T23:59:59.000Z

156

Reactive sticking coefficients of silane on silicon  

SciTech Connect

Reactive sticking coefficients (RSCs) were measured for silane and disilane on polycrystalline silicon for a wide range of temperature and flux (pressure) conditions. The data were obtained from deposition rate measurements using molecular beam scattering and a very low pressure cold wall reactor. The RSCs have non-Arrhenius temperature dependences and decreases with increasing flux at low (710/sup 0/) temperatures. A simple model involving dissociative adsorption of silane is consistent with these results. The results are compared with previous studies of the SiH/sub 4//Si(s) reaction.

Buss, R.J.; Ho, P.; Breiland, W.G.; Coltrin, M.E.

1988-09-15T23:59:59.000Z

157

Mechanistic Reactive Burn Modeling of Solid Explosives  

SciTech Connect

This report describes a computational framework for reactive burn modeling of solid explosives and the development of a test case where physical mechanisms represent RDX or RDX-based materials. The report is a sequel to LA-13794-MS, ''A Unifying Framework for Hot Spots and the Ignition of Energetic Materials,'' where we proposed a new approach to the building of a general purpose model that captures the essential features of the three primary origins of hot-spot formation: void collapse, shear banding, friction. The purpose of the present report is to describe the continuing task of coupling the unifying hot-spot model to hydrodynamic calculations to develop a mechanistic reactive burn model. The key components of the coupling include energy localization, the growth of hot spots, overall hot-spot behavior, and a phase-averaged mixture equation of state (EOS) in a Mie-Grueneisen form. The nucleation and growth of locally heated regions is modeled by a phenomenological treatment as well as a statistical model based on an exponential size distribution. The Mie-Grueneisen form of the EOS is one of many possible choices and is not a critical selection for implementing the model. In this report, model calculations are limited to proof-of-concept illustrations for shock loading. Results include (1) shock ignition and growth-to-detonation, (2) double shock ignition, and (3) quenching and reignition. A comparative study of Pop-plots is discussed based on the statistical model.

Y.Horie; Y.Hamate; D.Greening

2003-04-01T23:59:59.000Z

158

Reactive thermal waves in energetic materials  

SciTech Connect

Reactive thermal waves (RTWs) arise in several energetic material applications, including self-propagating high-temperature synthesis (SHS), high explosive cookoff, and the detonation of heterogeneous explosives. In this paper I exmaine ideal RTWs, by which I mean that (1) material motion is neglected, (2) the state dependence of reaction is Arrhenius in the temperature, and (3) the reaction rate is modulated by an arbitrary mass-fraction-based reaction progress function. Numerical simulations demonstrate that one's natural intuition, which is based mainly upon experience with inert materials and which leads one to expect diffusion processes to become relatively slow after a short time period, is invalid for high energy, state-sensitive reactive systems. Instead, theory predicts that RTWs can propagate at very high speeds. This result agrees with estimates for detonating heterogeneous explosives, which indicate that RTWs must spread from hot-spot nucleation sites at rates comparable to the detonation speed in order to produce experimentally-observed reaction zone thicknesses. Using dimensionless scaling and further invoking the high activation energy approximation, I obtain an analytic formula for the steady plane RTW speed from numerical calculations. I then compute the RTW speed for real explosives, and discuss aspects of their behavior.

Hill, Larry G [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

159

Mild coal pretreatment to improve liquefaction reactivity  

SciTech Connect

This report describes work completed during the fifth quarter of a three year project to study the effects of mild chemical pretreatment on coal dissolution reactivity during low severity liquefaction or coal/oil coprocessing. The overall objective of this research is to elucidate changes in the chemical and physical structure of coal by pretreating with methanol or other simple organic solvent and a trace amount of hydrochloric acid and measure the influence of these changes on coal dissolution reactivity. Work this quarter focused on analytical characterization of untreated and treated Wyodak subbituminous coal and Illinois {number sign}6 bituminous coal. Mossbauer spectroscopy and x-ray diffraction techniques were used to study the effect of methanol/HCl pretreatment on the composition of each coal's inorganic phase. Results from these studies indicated that calcite is largely removed during pretreatment, but that other mineral species such as pyrite are unaffected. This finding is significant, since calcite removal appears to directly correlate with low severity liquefaction enhancement. Further work will be performed to study this phenomenon in more detail.

Miller, R.L.

1991-01-01T23:59:59.000Z

160

Actinide and xenon reactivity effects in ATW high flux systems  

SciTech Connect

In this paper, initial system reactivity response to flux changes caused by the actinides and xenon are investigated separately for a high flux ATW system. The maximum change in reactivity after a flux change due to the effect of the changing quantities of actinides is generally at least two orders of magnitude smaller than either the positive or negative reactivity effect associated with xenon after a shutdown or start-up. In any transient flux event, the reactivity response of the system to xenon will generally occlude the response due to the actinides.

Woosley, M.; Olson, K.; Henderson, D. L.; Sailor, W. C. [Department of Mechanical, Aerospace, and Nuclear Engineering University of Virginia, Charlottesville, Virginia 22903 (United States); Department of Nuclear Engineering and Engineering Physics University of Wisconsin, Madison, Wisconsin 53706-1687 (United States); Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

1995-09-15T23:59:59.000Z

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Knudsen Layer Reduction of Fusion Reactivity Kim Molvig and Nelson...  

NLE Websites -- All DOE Office Websites (Extended Search)

fusion cross section determine Gamow peak in the fusion reactivity. 2 Inertially confined fusion systems typically have plasma fuel enveloped by a cold non-reacting region or...

162

SP-19: Electrochemistry of Enargite: Reactivity in Alkaline Solutions  

Science Conference Proceedings (OSTI)

The reactivity of enargite samples from Montana, US and Quiruvilca, Peru were studied under alkaline conditions, pH range of 8-13, using a cyclic voltammetry ...

163

Advancing Reactive Tracer Methods for Measuring Thermal Evolution...  

Open Energy Info (EERE)

History Facebook icon Twitter icon Advancing Reactive Tracer Methods for Measuring Thermal Evolution in CO2- and Water-Based Geothermal Reservoirs Geothermal Lab Call Project...

164

Chombo-Crunch: Advanced Simulation of Subsurface Flow and Reactive...  

NLE Websites -- All DOE Office Websites (Extended Search)

Chombo-Crunch: Advanced Simulation of Subsurface Flow and Reactive Transport Processes Associated with Carbon Sequestration PI Name: David Trebotich Institution: Lawrence Berkeley...

165

Instrumentation @ Catalysis: Reactivity and Structure Group | Chemistry  

NLE Websites -- All DOE Office Websites (Extended Search)

Instrumentation Instrumentation The Catalysis Group at BNL is leading research initiatives into the development of new tools and techniques that focus on the characterization of heterogeneous catalytic reactions and catalysts using imaging, spectroscopy and scattering techniques and integrated combinations of them under reaction conditions to unravel the morphology, chemical and structural properties, of catalysts, respectively. These efforts revolve around the use of synchrotron radiation (NSLS), electrons (CFN) and quantum tunneling tools with particular thrusts into imaging, spectroscopy and scattering. Groups Instrumentation(BNL) Three UHV chambers with diverse instrumentation for surface characterization: LEED, UPS, XPS, AES, TPD, ISS, PM-AP-IRRAS, Reactivity Cell. All the systems include ancillary instrumentation such as sputtering guns and metal evaporators. The IRRAS system was retrofitted with an ambient pressure (AP) cell on top of the UHV system. The sample can be prepared and characterized in UHV and then transfer in vacuum to the AP cell.

166

Artificial bee colony algorithm solution for optimal reactive power flow  

Science Conference Proceedings (OSTI)

Artificial bee colony (ABC) algorithm is an optimization algorithm based on the intelligent foraging behavior of honeybee swarm. Optimal reactive power flow (ORPF) based on ABC algorithm to minimize active power loss in power systems is studied in this ... Keywords: Artificial bee colony, Optimal reactive power flow, Penalty function, Power system

Kür?at Ayan; Ula? K?l?ç

2012-05-01T23:59:59.000Z

167

A formal approach for the development of reactive systems  

Science Conference Proceedings (OSTI)

Context: This paper deals with the development and verification of liveness properties on reactive systems using the Event-B method. By considering the limitation of the Event-B method to invariance properties, we propose to apply the language TLA^+ ... Keywords: Event-B method, Language TLA+, Liveness properties, Reactive systems, Refinement, Verification

Olfa Mosbahi; Leila Jemni Ben Ayed; Mohamed Khalgui

2011-01-01T23:59:59.000Z

168

MARKETS FOR REACTIVE POWER AND RELIABILITY: A WHITE PAPER  

E-Print Network (OSTI)

1 MARKETS FOR REACTIVE POWER AND RELIABILITY: A WHITE PAPER Engineering and Economics as efficient and optimal production and prices for real and reactive power. The purpose of this paper delivery of electric power. To accomplish this end, the paper opens with specification of an economic

169

Differential evolution approach for optimal reactive power dispatch  

Science Conference Proceedings (OSTI)

Differential evolution based optimal reactive power dispatch for real power loss minimization in power system is presented in this paper. The proposed methodology determines control variable settings such as generator terminal voltages, tap positions ... Keywords: Differential evolution, Loss minimization, Optimal power flow, Penalty function, Reactive power dispatch

M. Varadarajan; K. S. Swarup

2008-09-01T23:59:59.000Z

170

Reactive Power Compensation Technologies, State-of-the-Art Review  

E-Print Network (OSTI)

reactors to provide or absorb the required reactive power have been developed [7], [8], [9]. Also, the use static VAR generators, using power electronic technologies have been proposed and developed [7 compensators (SVC) consist of standard reactive power shunt elements (reactors and capacitors) which

Rudnick, Hugh

171

Variational reactivity estimates: new analyses and new results  

SciTech Connect

A modified form of the variational estimate of the reactivity worth ofa perturbation was previously developed to extend the range of applicability of variational perturbation theory for perturbations leading to negative reactivity worths. Recent numerical results challenged the assumptions behind the modified form. In this paper, more results are obtained, leading to the conclusion that sometimes the modified form extends the range ofapplicability of variational perturbation theory for positive reactivity worths as well, and sometimes the standard variational form is more accurate for negative-reactivity perturbations. In addition, this paper proves that using the exact generalized adjoint function would lead to an inaccurate variational reactivity estimate when the error in the first-order estimate is large; the standard generalized adjoint function, an approximation to the exact one, leads to Lore accurate results. This conclusion is also demonstrated numerically. Transport calculations use the PARTISN multi group discrete ordinates code

Favorite, Jeffrey A [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

172

Early maturation processes in coal. Part 2: Reactive dynamics simulations using the ReaxFF reactive force field on Morwell Brown coal structures  

E-Print Network (OSTI)

Early maturation processes in coal. Part 2: Reactive dynamics simulations using the ReaxFF reactive force field on Morwell Brown coal structures Elodie Salmon a , Adri C.T. van Duin b , François Lorant Brown coal using the ReaxFF reactive force field. We find that these reactive MD simulations

Goddard III, William A.

173

Reactive sticking coefficients of silane on silicon  

SciTech Connect

We have investigated the reaction of room-temperature silane and disilane on a hot polycrystalline silicon surface using both a collision-free molecular beam and a very low pressure CVD cell. Reactive sticking coefficients were obtained from deposition rate data over a wide range of temperatures and silane (disilane) fluxes. The RSCs are substantially less than one, ranging from 6 x 10/sup -5/ to 4 x 10/sup -2/. For silane we observed curved Arrhenius plots with slopes decreasing from approx.60 kcal mol/sup -1/ at low temperatures to approx.2 kcal mol/sup -1/ at higher temperatures. The RSCs are independent of flux (pressure) at 1040/sup 0/C, but vary as flux to the approx.-1/2 power at 710/sup 0/C. A model comprised of a dissociative adsorption mechanism with competing associative desorption and reaction was found to give reasonable agreement. For disilane, we observed RSCs that were roughly ten times higher than those for silane. We also observed a curved Arrhenius plot and a flux dependence at 710/sup 0/C for disilane. 22 refs., 5 figs.

Buss, R.J.; Ho, P.; Breiland, W.G.; Coltrin, M.E.

1987-01-01T23:59:59.000Z

174

Reactivity of coals under coprocessing conditions  

DOE Green Energy (OSTI)

In the recent years greater interest has developed for processes involving coal and petroleum fractions to produce distillate fuels. Coprocessing is especially attractive as a direct liquefaction process because it involves the use of heavy petroleum fractions, so both coal and heavy petroleum resids are upgraded simultaneously. The main distinction of coprocessing from other direct liquefaction processes is that coprocessing is more complex from a chemical standpoint than direct liquefaction processes which use traditional solvents, due to the greater variety of hydrocarbons (aromatic from the coal and aliphatics from the petroleum) present in the system. Therefore, need arises for better understanding of the chemical and physical interactions during coprocessing. The aim of the present study is to examine the influence of reaction conditions, coal and petroleum resid properties as well as the compatibility of the coal/petroleum resid pairs in terms of structural components on total coal conversion. Special focus will be given to the reactivity of coals and interaction of the coal and resid which lead to anisotropic coke.

Tomic, J.; Schobert, H.H.

1992-06-01T23:59:59.000Z

175

Reactivity of coals under coprocessing conditions  

DOE Green Energy (OSTI)

In the recent years greater interest has developed for processes involving coal and petroleum fractions to produce distillate fuels. Coprocessing is especially attractive as a direct liquefaction process because it involves the use of heavy petroleum fractions, so both coal and heavy petroleum resids are upgraded simultaneously. The main distinction of coprocessing from other direct liquefaction processes is that coprocessing is more complex from a chemical standpoint than direct liquefaction processes which use traditional solvents, due to the greater variety of hydrocarbons (aromatic from the coal and aliphatics from the petroleum) present in the system. Therefore, need arises for better understanding of the chemical and physical interactions during coprocessing. The aim of the present study is to examine the influence of reaction conditions, coal and petroleum resid properties as well as the compatibility of the coal/petroleum resid pairs in terms of structural components on total coal conversion. Special focus will be given to the reactivity of coals and interaction of the coal and resid which lead to anisotropic coke.

Tomic, J.; Schobert, H.H.

1992-01-01T23:59:59.000Z

176

NREL: Technology Transfer - NREL Partnering with GreenVolts to ...  

National Renewable Energy ... to co-develop NREL's patents and bring this new technology to market. ... specifications and process information, ...

177

Design and Assessment of Volt-VAR Optimization Systems  

Science Conference Proceedings (OSTI)

Utilities are seeking to improve the overall efficiency and performance of the distribution system to squeeze more capacity out of existing facilities and to accommodate high penetrations of distributed energy resources, including renewable generating sources with highly variable output. Distribution voltage optimization (DVO) will play a major role in accomplishing these objectives without compromising safety, asset protection, and operating constraints (such as maximum loading and minimum/maximum volta...

2011-12-30T23:59:59.000Z

178

Physics and Cosmology : the Milli-Electron-Volt Scale  

E-Print Network (OSTI)

A short review about vacuum energy and the cosmological constant is presented. The observed acceleration of the universe introduces a new meV energy scale. The problem is that, theoretically, the predicted vacuum energy is many orders of magnitude larger than $10^{-3}$ eV. The problem is a link between two Standard Models, namely the Standard Model of Particles and their Interactions (where the vacuum energy appears) and the Standard Cosmological Model (where a cosmological constant is a good fit to data), and perhaps it is a clue in our search for new physics.

Eduard Masso

2009-02-27T23:59:59.000Z

179

Laser Diode Cathode Laser Diode Anode +5 Volts  

E-Print Network (OSTI)

the high performance you expect from a Wavelength component with two distinct improvements: low voltage operation from +5 V DC, and an Active Current Limit. Operating from a single +5 V supply minimizes heat dissipation. Modular packaging makes it easy to integrate the PLD into your system. For applications that require a higher forward voltage, a separate laser diode power supply input lets you provide a higher compliance voltage. The Active Current Limit not only protects your laser diode, but ensures that you are operating with maximum stability. When the laser current reaches the level set by the Limit I Trimpot, the output disables and the Limit LED and Limit Status indicate the current limit has been reached. Two photodiode ranges provide variable sensitivities for optimum operation. You can maintain excellent stability when operating in both constant current and constant power mode. All trimpots and switches are easily accessible and offer precision control. A slow start circuit, mechanical shorting relay, and Active Current Limit offer maximum protection for your laser diode even when power is removed.

H; pin Power Ground; Lim I Adj; I Disabled

2010-01-01T23:59:59.000Z

180

Feasibility study for mega-electron-volt electron beam tomography  

SciTech Connect

Electron beam tomography is a promising imaging modality for the study of fast technical processes. But for many technical objects of interest x rays of several hundreds of keV energy are required to achieve sufficient material penetration. In this article we report on a feasibility study for fast electron beam computed tomography with a 1 MeV electron beam. The experimental setup comprises an electrostatic accelerator with beam optics, transmission target, and a single x-ray detector. We employed an inverse fan-beam tomography approach with radiographic projections being generated from the linearly moving x-ray source. Angular projections were obtained by rotating the object.

Hampel, U. [Institute of Fluid Dynamics, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstrasse 400, 01328 Dresden (Germany); AREVA Endowed Chair of Imaging Techniques in Energy and Process Engineering, Technische Universitaet Dresden, 01062 Dresden (Germany); Baertling, Y.; Hoppe, D. [Institute of Fluid Dynamics, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstrasse 400, 01328 Dresden (Germany); Kuksanov, N.; Fadeev, S.; Salimov, R. [Budker Institute of Nuclear Physics of Siberian Branch of Russian Academy of Science, Lavrentiev av. 11, Novosibirsk 630090 (Russian Federation)

2012-09-15T23:59:59.000Z

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Economic Impact Assessment of the NIST's Josephson Volt ...  

Science Conference Proceedings (OSTI)

... Department of Energy's weapons development laboratories, represent ... significant share of annual revenue is ... Industry & Trade Outlook '99, McGraw ...

2012-10-21T23:59:59.000Z

182

NREL: Technology Transfer - NREL, HelioVolt Receive ...  

A revolutionary thin-film photovoltaic (PV) manufacturing process developed through a partnership between the National Renewable Energy Laboratory ...

183

Method for generating a highly reactive plasma for exhaust gas aftertreatment and enhanced catalyst reactivity  

DOE Patents (OSTI)

A method for non-thermal plasma aftertreatment of exhaust gases the method comprising the steps of providing short risetime, high frequency, high power bursts of low-duty factor microwaves sufficient to generate a plasma discharge and passing a gas to be treated through the discharge so as to cause dissociative reduction of the exhaust gases and enhanced catalyst reactivity through application of the pulsed microwave fields directly to the catalyst material sufficient to cause a polarizability catastrophe and enhanced heating of the metal crystallite particles of the catalyst, and in the presence or absence of the plasma. The invention also includes a reactor for aftertreatment of exhaust gases.

Whealton, John H. (Oak Ridge, TN); Hanson, Gregory R. (Clinton, TN); Storey, John M. (Oak Ridge, TN); Raridon, Richard J. (Oak Ridge, TN); Armfield, Jeffrey S. (Ypsilanti, MI); Bigelow, Timothy S. (Knoxville, TN); Graves, Ronald L. (Knoxville, TN)

2002-01-01T23:59:59.000Z

184

Reactivity Control Schemes for Fast Spectrum Space Nuclear Reactors  

Science Conference Proceedings (OSTI)

Several different reactivity control schemes are considered for future space nuclear reactor power systems. Each of these control schemes uses a combination of boron carbide absorbers and/or beryllium oxide reflectors to achieve sufficient reactivity swing to keep the reactor subcritical during launch and to provide sufficient excess reactivity to operate the reactor over its expected 7–15 year lifetime. The size and shape of the control system directly impacts the size and mass of the space reactor's reflector and shadow shield

Aaron E. Craft; Jeffrey C. King

2008-01-01T23:59:59.000Z

185

Assessment of the Economic Potential of Microgrids for Reactive Power Supply  

E-Print Network (OSTI)

of Commercial Building Microgrids,” IEEE Transactions onEconomic Potential of Microgrids for Reactive Power Supplyof creating an incentive for microgrids to provide reactive

Appen, Jan von

2012-01-01T23:59:59.000Z

186

Synthesis of Sm-Fe-N Hard Magnets by Reactive Mechanical Milling  

Science Conference Proceedings (OSTI)

In this study, we have performed reactive mechanical milling on Sm2Fe17 alloy under hydrogen atmosphere. After reactive mechanical milling, the Sm2Fe17 ...

187

Photo of the Week: Reactive Ion Etching | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Reactive Ion Etching Reactive Ion Etching Photo of the Week: Reactive Ion Etching October 17, 2013 - 1:26pm Addthis Have you ever heard of Laue lenses? These multilayer lenses are used to focus high-intensity x-ray beams to show the details of nano material structures. In this photo, the drop-like domes were carved through a process called reactive ion etching, which produced the striped bubbles you see in the Laue lens. The prototype in this image helped scientists perfect the process of creating lenses so precise that scientists are able to focus x-rays to within a single nanometer. | Photo courtesy of Brookhaven National Laboratory. Have you ever heard of Laue lenses? These multilayer lenses are used to focus high-intensity x-ray beams to show the details of nano material

188

Radiation Chemistry of Ionic Liquids: Reactivity of Primary Species  

NLE Websites -- All DOE Office Websites (Extended Search)

Liquids: Reactivity of Primary Species Liquids: Reactivity of Primary Species James F. Wishart In "Ionic Liquids as Green Solvents: Progress and Prospects" Rogers, R. D. and Seddon, K. R. , Eds.; ACS Symp. Ser. 856, Ch. 31, pp. 381-395, American Chemical Society, Washington, DC, 2003. (ISBN 0-84123-856-1) [Information about the book] Abstract: An understanding of the radiation chemistry of ionic liquids is important for development of their applications in radioactive material processing and for the application of pulse radiolysis techniques to the general study of chemical reactivity in ionic liquids. The distribution of primary radiolytic species and their reactivities determine the yields of ultimate products and the radiation stability of a particular ionic liquid. This chapter introduces some principles of radiation chemistry and the

189

A-26: Nanoindentation Investigation of the Reactive Pulsed Laser ...  

Science Conference Proceedings (OSTI)

... of the Reactive Pulsed Laser Deposited Superconducting Niobium Nitride Thin Films. Author(s) ... A-33: Modeling of a Displacive Transformation within Continuous ... Dye-Sensitized Solar Cells by Introducing a TiN Nanocrystalline Thin Film.

190

Pre-plated reactive diffusion-bonded battery electrode plaques  

SciTech Connect

A high strength, metallic fiber battery plaque is made using reactive diffusion bonding techniques, where a substantial amount of the fibers are bonded together by an iron-nickel alloy.

Maskalick, Nicholas J. (Pittsburgh, PA)

1984-01-01T23:59:59.000Z

191

Land Use and Reactive Nitrogen Discharge: Effects of Dietary Choices  

Science Conference Proceedings (OSTI)

Modern agriculture alters natural biological and geophysical processes, with magnitudes proportional to its spatial extent. Cultivation is also the main cause of artificially enhanced reactive nitrogen (Nr) availability in natural ecosystems. ...

Gidon Eshel; Pamela A. Martin; Esther E. Bowen

2010-12-01T23:59:59.000Z

192

Reactive Reserve Requirements and Optimal Allocation Among Resources  

Science Conference Proceedings (OSTI)

Voltage stability is a major concern in power system operation, and the need to maintain it limits power transfers in the prevailing open access environment. In a power system with significant induction motor loads, voltage instability can be manifested either in the form of delayed voltage recovery or voltage collapse. Inadequate reactive supply is a major factor in causing these problems. Reactive supply is an important ingredient in maintaining healthy power system voltages and facilitating power tran...

2010-12-01T23:59:59.000Z

193

(Electronic structure and reactivities of transition metal clusters)  

DOE Green Energy (OSTI)

The following are reported: theoretical calculations (configuration interaction, relativistic effective core potentials, polyatomics, CASSCF); proposed theoretical studies (clusters of Cu, Ag, Au, Ni, Pt, Pd, Rh, Ir, Os, Ru; transition metal cluster ions; transition metal carbide clusters; bimetallic mixed transition metal clusters); reactivity studies on transition metal clusters (reactivity with H{sub 2}, C{sub 2}H{sub 4}, hydrocarbons; NO and CO chemisorption on surfaces). Computer facilities and codes to be used, are described. 192 refs, 13 figs.

Not Available

1992-01-01T23:59:59.000Z

194

[Electronic structure and reactivities of transition metal clusters  

DOE Green Energy (OSTI)

The following are reported: theoretical calculations (configuration interaction, relativistic effective core potentials, polyatomics, CASSCF); proposed theoretical studies (clusters of Cu, Ag, Au, Ni, Pt, Pd, Rh, Ir, Os, Ru; transition metal cluster ions; transition metal carbide clusters; bimetallic mixed transition metal clusters); reactivity studies on transition metal clusters (reactivity with H{sub 2}, C{sub 2}H{sub 4}, hydrocarbons; NO and CO chemisorption on surfaces). Computer facilities and codes to be used, are described. 192 refs, 13 figs.

Not Available

1992-08-01T23:59:59.000Z

195

Reactive burn models and ignition & growth concept  

SciTech Connect

Plastic-bonded explosives are heterogeneous materials. Experimentally, shock initiation is sensitive to small amounts of porosity, due to the formation of hot spots (small localized regions of high temperature). This leads to the Ignition and Growth concept, introduced by Lee and Tarver in 1980, as the basis for reactive burn models. A homogeneized burn rate needs to account for three mesoscale physical effects (i) the density of burnt hot spots, which depends on the lead shock strength; (ii) the growth of the burn fronts triggered by hot spots, which depends on the local deflagration speed; (iii) a geometric factor that accounts for the overlap of deflagration wavelets from adjacent hot spots. These effects can be combined and the burn model defined by specifying the reaction progress variable {lambda}(t) as a function of a dimensionless reaction length {tau}{sub hs}(t)/{ell}{sub hs}, rather than by xpecifying an explicit burn rate. The length scale {ell}{sub hs} is the average distance between hot spots, which is proportional to [N{sub hs}(P{sub s})]{sup -1/3}, where N{sub hs} is the number density of hot spots activated by the lead shock. The reaction length {tau}{sub hs}(t) = {line_integral}{sub 0}{sup t} D(P(t'))dt' is the distance the burn front propagates from a single hot spot, where D is the deflagration speed and t is the time since the shock arrival. A key implementation issue is how to determine the lead shock strength in conjunction with a shock capturing scheme. They have developed a robust algorithm for this purpose based on the Hugoniot jump condition for the energy. The algorithm utilizes the time dependence of density, pressure and energy within each cell. The method is independent of the numerical dissipation used for shock capturing. It is local and can be used in one or more space dimensions. The burn model has a small number of parameters which can be calibrated to fit velocity gauge data from shock initiation experiments.

Menikoff, Ralph S [Los Alamos National Laboratory; Shaw, Milton S [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

196

Third (March 2006) Coring and Analysis of Zero-Valent Iron Permeable Reactive Barrier, Monticello, Utah  

Energy.gov (U.S. Department of Energy (DOE))

Third (March 2006) Coring and Analysis of Zero-Valent Iron Permeable Reactive Barrier, Monticello, Utah

197

Reactive behavior in object-oriented applications: an analysis and a research roadmap  

Science Conference Proceedings (OSTI)

Reactive applications are difficult to implement. Traditional solutions based on event systems and the Observer pattern have a number of inconveniences, but programmers bear them in return for the benefits of OO design. On the other hand, reactive approaches ... Keywords: functional-reactive programming, incremental computation, object-oriented programming, reactive programming

Guido Salvaneschi; Mira Mezini

2013-03-01T23:59:59.000Z

198

Ionic Liquids and Ionizing Radiation: Reactivity of Highly Energetic  

NLE Websites -- All DOE Office Websites (Extended Search)

Ionizing Radiation: Reactivity of Highly Energetic Ionizing Radiation: Reactivity of Highly Energetic Species James F. Wishart J. Phys. Chem. Lett. 1, 3225-3231 (2010). [Find paper at ACS Publications] or use ACS Articles on Request View the video on this Perspective article at The Journal of Physical Chemistry Letters (5:03) Selected for the ACS Special Virtual Issue on Ionic Liquids (March 2011). Abstract: Due to their unique properties, ionic liquids present many opportunities for basic research on the interactions of radiation with materials under conditions not previously available. At the same time, there are practical applied reasons for characterizing, understanding, and being able to predict how ionic-liquid-based devices and industrial-scale systems will perform under conditions of extreme reactivity, including radiation. This

199

Options for Control of Reactive Power by Distributed Photovoltaic Generators  

E-Print Network (OSTI)

High penetration levels of distributed photovoltaic(PV) generation on an electrical distribution circuit present several challenges and opportunities for distribution utilities. Rapidly varying irradiance conditions may cause voltage sags and swells that cannot be compensated by slowly responding utility equipment resulting in a degradation of power quality. Although not permitted under current standards for interconnection of distributed generation, fast-reacting, VAR-capable PV inverters may provide the necessary reactive power injection or consumption to maintain voltage regulation under difficult transient conditions. As side benefit, the control of reactive power injection at each PV inverter provides an opportunity and a new tool for distribution utilities to optimize the performance of distribution circuits, e.g. by minimizing thermal losses. We discuss and compare via simulation various design options for control systems to manage the reactive power generated by these inverters. An important design de...

Sulc, Petr; Backhaus, Scott; Chertkov, Michael

2010-01-01T23:59:59.000Z

200

Internal structure, hygroscopic and reactive properties of mixed sodium  

NLE Websites -- All DOE Office Websites (Extended Search)

Internal structure, hygroscopic and Internal structure, hygroscopic and reactive properties of mixed sodium methanesulfonate-sodium chloride particles Internal structure, hygroscopic and reactive properties of mixed sodium methanesulfonate-sodium chloride particles Print Friday, 13 May 2011 00:00 Scientists recently combined experimental approaches and molecular dynamics modeling to gain new insights into the internal structure of sea salt particles and relate it to their fundamental chemical reactivity in the atmosphere. This research shows that surface enhancement or depletion of chemical components in marine particles can occur because of the difference in the chemical nature of the species. Because the atmospheric chemistry of the salt particles takes place at the gas-particle interface, understanding their complex surfaces provides new insights about their effect on the environment and climate change. Article Link.

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

OPF for reactive pricing studies on the NGC system  

SciTech Connect

Retail transmission services like those being provided by the National Grid Company (NGC) in England and Wales pose new challenges for the pricing of reactive power supply. A reactive power market approach has been proposed by NGC and continues to be evaluated. Such an approach includes a novel requirement for transmission constrained economic dispatch of VArs, a problem in the security constrained optimal power flow (OPF) class. The problem formulations handled by the OPF package in use could not accommodate NGC`s requirements. This paper describes the reactive pricing problem being addressed, the modeling requirements, and the resulting extensions made to the OPF formulation and package. It discusses the test results obtained to date on the NGC system.

Dandachi, N.H.; Rawlins, M.J. [National Grid Co., Sindlesham (United Kingdom). Control Technology Centre; Alsac, O.; Prais, M.; Stott, B. [PCA Corp., Mesa, AZ (United States)

1996-02-01T23:59:59.000Z

202

Method and apparatus for measuring reactivity of fissile material  

DOE Patents (OSTI)

Given are a method and apparatus for measuring nondestructively and noninvasively (i.e., using no internal probing) the burnup, reactivity, or fissile content of any material which emits neutrons and which has fissionable components. The assay is accomplished by altering the return flux of neutrons into the fuel assembly by means of changing the reflecting material. The existing passive neutron emissions in the material being assayed are used as the source of interrogating neutrons. Two measurements of either emitted neutron or emitted gamma-ray count rates are made and are then correlated to either reactivity, burnup, or fissionable content of the material being assayed, thus providing a measurement of either reactivity, burnup, or fissionable content of the material being assayed. Spent fuel which has been freshly discharged from a reactor can be assayed using this method and apparatus. Precisions of 1000 MWd/tU appear to be feasible.

Lee, D.M.; Lindquist, L.O.

1982-09-07T23:59:59.000Z

203

Effect of superbanana diffusion on fusion reactivity in stellarators  

Science Conference Proceedings (OSTI)

Fusion reactivity is usually obtained using a Maxwellian distribution. However, energy-dependent radial diffusion can modify the energy distribution. Superbanana diffusion is energy-dependent and occurs in nonaxisymmetric magnetic confinement devices, such as stellarators, because of ripple-trapped particles which can take large steps between collisions. In this paper, the D-T fusion reactivity is calculated using a non-Maxwellian energy distribution obtained by solving the Fokker-Planck equation numerically, including radial superbanana diffusion as well as energy scattering. The ions in the tail of the distribution, with energies larger than thermal, which are most needed for fusion, are depleted by superbanana diffusion. In this paper, it is shown that the D-T fusion reactivity is reduced by tail ion depletion due to superbanana diffusion, by roughly a factor of 0.5 for the parameters used in the calculation.

Hinton, Fred L. [Center for Astrophysics and Space Sciences, University of California, San Diego, La Jolla, California 92093-0424 (United States)

2012-08-15T23:59:59.000Z

204

Enhanced durability and reactivity for zinc ferrite desulfurization sorbent  

Science Conference Proceedings (OSTI)

AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

Jha, M.C.; Berggren, M.H.

1989-05-02T23:59:59.000Z

205

Dielectric covered hairpin probe for its application in reactive plasmas  

Science Conference Proceedings (OSTI)

The hairpin probe is a well known technique for measuring local electron density in low temperature plasmas. In reactive plasmas, the probe characteristics are affected by surface sputtering, contamination, and secondary electron emission. At higher densities, the plasma absorbs the entire electromagnetic energy of hairpin and hence limits the density measurements. These issues can be resolved by covering the hairpin surface with a thin layer of dielectric. In this letter, the dielectric contribution to the probe characteristics is incorporated in a theory which is experimentally verified. The dielectric covering improves the performance of probe and also allows the hairpin tip to survive in reactive plasma where classical electrical probes are easily damaged.

Gogna, G. S.; Gaman, C.; Turner, M. M. [NCPST, School of Physical Sciences, Dublin City University, Dublin 9 (Ireland); Karkari, S. K. [Institute for Plasma Research Center, Bhat Gandhinagar, Gujarat 382428 (India)

2012-07-23T23:59:59.000Z

206

Local control of reactive power by distributed photovoltaic generators  

SciTech Connect

High penetration levels of distributed photovoltaic (PV) generation on an electrical distribution circuit may severely degrade power quality due to voltage sags and swells caused by rapidly varying PV generation during cloud transients coupled with the slow response of existing utility compensation and regulation equipment. Although not permitted under current standards for interconnection of distributed generation, fast-reacting, VAR-capable PV inverters may provide the necessary reactive power injection or consumption to maintain voltage regulation under difficult transient conditions. As side benefit, the control of reactive power injection at each PV inverter provides an opportunity and a new tool for distribution utilities to optimize the performance of distribution circuits, e.g. by minimizing thermal losses. We suggest a local control scheme that dispatches reactive power from each PV inverter based on local instantaneous measurements of the real and reactive components of the consumed power and the real power generated by the PVs. Using one adjustable parameter per circuit, we balance the requirements on power quality and desire to minimize thermal losses. Numerical analysis of two exemplary systems, with comparable total PV generation albeit a different spatial distribution, show how to adjust the optimization parameter depending on the goal. Overall, this local scheme shows excellent performance; it's capable of guaranteeing acceptable power quality and achieving significant saving in thermal losses in various situations even when the renewable generation in excess of the circuit own load, i.e. feeding power back to the higher-level system.

Chertkov, Michael [Los Alamos National Laboratory; Turitsyn, Konstantin [Los Alamos National Laboratory; Sulc, Petr [Los Alamos National Laboratory; Backhaus, Scott [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

207

Development of a model for reactive emissions from industrial stacks  

Science Conference Proceedings (OSTI)

We have developed a model, CAPAS, capable of estimating short-term concentrations of primary and secondary pollutants resulting from point source emissions. The model is designed to simulate the complex interaction of plume dispersion and non-linear ... Keywords: Air pollutants, Dispersion models, Non-linear chemistry, Plume reactivity, Stiff solvers

Luis E. Olcese; Beatriz M. Toselli

2005-10-01T23:59:59.000Z

208

Reactive transport in surface sediments I. Mexity and software quality  

Science Conference Proceedings (OSTI)

Analysis of three recent diagenetic model codes (OMEXDIA, CANDI and STEADYSED) revealed that codes have a rigid, static and problem-specific character, leaving little autonomy for the application user. The resulting lack of flexibility and extensibility, ... Keywords: early diagenesis, object-oriented design, problem-solving environment, reactive transport modelling, software quality assurance

Filip J. R. Meysman; Jack J. Middelburg; Peter M. J. Herman; Carlo H. R. Heip

2003-04-01T23:59:59.000Z

209

Modeling and Verification of Reactive Systems using Rebeca  

Science Conference Proceedings (OSTI)

Actor-based modeling has been successfully applied to the representation of concurrent and distributed systems. Besides having an appropriate and efficient way for modeling these systems, one needs a formal verification approach for ensuring their correctness. ... Keywords: actor model, compositional verification, model checking, property preserving abstraction, reactive systems

Marjan Sirjani; Ali Movaghar; Amin Shali; Frank S. de Boer

2004-12-01T23:59:59.000Z

210

Method and apparatus for measuring reactivity of fissile material  

DOE Patents (OSTI)

Given are a method and apparatus for measuring nondestructively and non-invasively (i.e., using no internal probing) the burnup, reactivity, or fissile content of any material which emits neutrons and which has fissionable components. No external neutron-emitting interrogation source or fissile material is used and no scanning is required, although if a profile is desired scanning can be used. As in active assays, here both reactivity and content of fissionable material can be measured. The assay is accomplished by altering the return flux of neutrons into the fuel assembly. The return flux is altered by changing the reflecting material. The existing passive neutron emissions in the material being assayed are used as the source of interrogating neutrons. Two measurements of either emitted neutron or emitted gamma-ray count rates are made and are then correlated to either reactivity, burnup, or fissionable content of the material being assayed, thus providing a measurement of either reactivity, burnup, or fissionable content of the material being assayed. Spent fuel which has been freshly discharged from a reactor can be assayed using this method and apparatus. Precisions of 1000 MWd/tU appear to be feasible.

Lee, David M. (Los Alamos, NM); Lindquist, Lloyd O. (Santa Fe, NM)

1985-01-01T23:59:59.000Z

211

Enhanced durability and reactivity for zinc ferrite desulfurization sorbent  

Science Conference Proceedings (OSTI)

AMAX Research Development Center (AMAX R D) investigated methods for enhancing the reactivity and durability of zinc ferrite desulfurization sorbents. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For this program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such as size, strength, and specific surface area during 10 cycles of sulfidation and oxidation. Two base case sorbents, a spherical pellet and a cylindrical extrude used in related METC-sponsored projects, were used to provide a basis for the aimed enhancement in durability and reactivity. Sorbent performance was judged on the basis of physical properties, single particle kinetic studies based on thermogravimetric (TGA) techniques, and multicycle bench-scale testing of sorbents. A sorbent grading system was utilized to quantify the characteristics of the new sorbents prepared during the program. Significant enhancements in both reactivity and durability were achieved for the spherical pellet shape over the base case formulation. Overall improvements to reactivity and durability were also made to the cylindrical extrude shape. The primary variables which were investigated during the program included iron oxide type, zinc oxide:iron oxide ratio, inorganic binder concentration, organic binder concentration, and induration conditions. The effects of some variables were small or inconclusive. Based on TGA studies and bench-scale tests, induration conditions were found to be very significant.

Berggren, M.H.; Jha, M.C.

1989-10-01T23:59:59.000Z

212

Alternatives for Mending a Permeable Reactive Barrier at a Former Uranium  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Alternatives for Mending a Permeable Reactive Barrier at a Former Alternatives for Mending a Permeable Reactive Barrier at a Former Uranium Milling Site: Monticello, Utah Alternatives for Mending a Permeable Reactive Barrier at a Former Uranium Milling Site: Monticello, Utah Alternatives for Mending a Permeable Reactive Barrier at a Former Uranium Milling Site: Monticello, Utah Alternatives for Mending a Permeable Reactive Barrier at a Former Uranium Milling Site: Monticello, Utah More Documents & Publications Performance Assessment and Recommendations for Rejuvenation of a Permeable Reactive Barrier: Cotter Corporation's Cañon City, Colorado, Uranium Mill Performance Assessment and Recommendations for Rejuvenation of a Permeable Reactive Barrier: Cotter Corporation's Cañon City, Colorado, Uranium Mill Phase II: Performance Evaluation of Permeable Reactive Barriers and

213

Alternatives for Mending a Permeable Reactive Barrier at a Former Uranium  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Alternatives for Mending a Permeable Reactive Barrier at a Former Alternatives for Mending a Permeable Reactive Barrier at a Former Uranium Milling Site: Monticello, Utah Alternatives for Mending a Permeable Reactive Barrier at a Former Uranium Milling Site: Monticello, Utah Alternatives for Mending a Permeable Reactive Barrier at a Former Uranium Milling Site: Monticello, Utah Alternatives for Mending a Permeable Reactive Barrier at a Former Uranium Milling Site: Monticello, Utah More Documents & Publications Performance Assessment and Recommendations for Rejuvenation of a Permeable Reactive Barrier: Cotter Corporation's Cañon City, Colorado, Uranium Mill Performance Assessment and Recommendations for Rejuvenation of a Permeable Reactive Barrier: Cotter Corporation's Cañon City, Colorado, Uranium Mill Final Report Phase II: Performance Evaluation of Permeable Reactive

214

Using toughreact to model reactive fluid flow and geochemical transport in hydrothermal systems  

E-Print Network (OSTI)

multiphase flow, solute transport and reactive chemistry in porousmultiphase fluid flow, mass transport and chemical reactions, (2) reactive fluid flow and transport in fractured rocks as well as porous

Xu, Tianfu; Sonnenthal, Eric; Spycher, Nicolas; Pruess, Karsten

2003-01-01T23:59:59.000Z

215

Catalytic and reactive polypeptides and methods for their preparation and use  

DOE Patents (OSTI)

Catalytic and reactive polypeptides include a binding site specific for a reactant or reactive intermediate involved in a chemical reaction of interest. The polypeptides further include at least one active functionality proximate the bi.

Schultz, Peter (Oakland, CA)

1993-01-01T23:59:59.000Z

216

Incorporation of plug in hybrid electric vehicle in the reactive power market  

Science Conference Proceedings (OSTI)

This paper incorporates plug in hybrid electric vehicle(PHEV) in the reactive power market. The PHEV capability curve is first extracted considering the operation limit of PHEV. In order to offer price in the reactive power market

H. Feshki Farahani; H. A. Shayanfar; M. S. Ghazizadeh

2012-01-01T23:59:59.000Z

217

Reactive Plasma-Aided Fabrication of ZnO for Solar Cells Applications  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, Materials Science & Technology 2009. Symposium, Multifunctional Oxide. Presentation Title, Reactive Plasma-Aided Fabrication of ...

218

24 Hour Day-Ahead Reactive Power Forecasting and Optimal Scheduling  

Science Conference Proceedings (OSTI)

Reactive power management affects not only the system voltage profiles but also system efficiencies. Changes in the flow of reactive power have an influence on system losses. Reactive power forecasting and optimal scheduling of power system control elements can be conducted to efficiently and reliably transfer power across the system. The tool discussed in this report optimizes the power system to produce a security-constrained case, reduce losses, increase reactive reserve, and securely maintain ...

2013-12-29T23:59:59.000Z

219

Efficient and Reliable Reactive Power Supply and Consumption -- Insights from an Integrated Program of Engineering and Economic Research  

E-Print Network (OSTI)

need to establish real-time prices for reactive power toWe find that nodal real-time prices for reactive power willfind that non-zero real-time prices for reactive power will

2008-01-01T23:59:59.000Z

220

Catalytic destruction of groundwater contaminants in reactive extraction wells  

DOE Green Energy (OSTI)

A system for remediating groundwater contaminated with halogenated solvents, certain metals and other inorganic species based on catalytic reduction reactions within reactive well bores. The groundwater treatment uses dissolved hydrogen as a reducing agent in the presence of a metal catalyst, such a palladium, to reduce halogenated solvents (as well as other substituted organic compounds) to harmless species (e.g., ethane or methane) and immobilize certain metals to low valence states. The reactive wells function by removing water from a contaminated water-bearing zone, treating contaminants with a well bore using catalytic reduction, and then reinjecting the treated effluent into an adjacent water-bearing zone. This system offers the advantages of a compact design with a minimal surface footprint (surface facilities) and the destruction of a broad suite of contaminants without generating secondary waste streams.

McNab, Jr., Walt W. (Concord, CA); Reinhard, Martin (Stanford, CA)

2002-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Modeling Routing Overhead Generated by Wireless Reactive Routing Protocols  

E-Print Network (OSTI)

In this paper, we have modeled the routing over- head generated by three reactive routing protocols; Ad-hoc On-demand Distance Vector (AODV), Dynamic Source Routing (DSR) and DYnamic MANET On-deman (DYMO). Routing performed by reactive protocols consists of two phases; route discovery and route maintenance. Total cost paid by a protocol for efficient routing is sum of the cost paid in the form of energy consumed and time spent. These protocols majorly focus on the optimization performed by expanding ring search algorithm to control the flooding generated by the mechanism of blind flooding. So, we have modeled the energy consumed and time spent per packet both for route discovery and route maintenance. The proposed framework is evaluated in NS-2 to compare performance of the chosen routing protocols.

Javaid, Nadeem; Javaid, Akmal; Malik, Shahzad A

2011-01-01T23:59:59.000Z

222

Tracking thermal fronts with temperature-sensitive, chemically reactive tracers  

DOE Green Energy (OSTI)

Los Alamos is developing tracer techniques using reactive chemicals to track thermal fronts in fractured geothermal reservoirs. If a nonadsorbing tracer flowing from the injection to production well chemically reacts, its reaction rate will be a strong function of temperature. Thus the extent of chemical reaction will be greatest early in the lifetime of the system, and less as the thermal front progresses from the injection to production well. Early laboratory experiments identified tracers with chemical kinetics suitable for reservoirs in the temperature range of 75 to 100/sup 0/C. Recent kinetics studies have focused on the kinetics of hydrolysis of derivatives of bromobenzene. This class of reactions can be used in reservoirs ranging in temperature from 150 to 275/sup 0/C, which is of greater interest to the geothermal industry. Future studies will include laboratory adsorption experiments to identify possibly unwanted adsorption on granite, development of sensitive analytical techniques, and a field demonstration of the reactive tracer concept.

Robinson, B.A.; Birdsell, S.A.

1987-01-01T23:59:59.000Z

223

Solid polymer battery electrolyte and reactive metal-water battery  

SciTech Connect

In one implementation, a reactive metal-water battery includes an anode comprising a metal in atomic or alloy form selected from the group consisting of periodic table Group 1A metals, periodic table Group 2A metals and mixtures thereof. The battery includes a cathode comprising water. Such also includes a solid polymer electrolyte comprising a polyphosphazene comprising ligands bonded with a phosphazene polymer backbone. The ligands comprise an aromatic ring containing hydrophobic portion and a metal ion carrier portion. The metal ion carrier portion is bonded at one location with the polymer backbone and at another location with the aromatic ring containing hydrophobic portion. The invention also contemplates such solid polymer electrolytes use in reactive metal/water batteries, and in any other battery.

Harrup, Mason K. (Idaho Falls, ID); Peterson, Eric S. (Idaho Falls, ID); Stewart, Frederick F. (Idaho Falls, ID)

2000-01-01T23:59:59.000Z

224

Application of genetic algorithms for optimal reactive power planning of doubly fed induction generators  

Science Conference Proceedings (OSTI)

This paper describes optimal reactive power control of a doubly fed induction generator (DFIG), which is widely used in a distributed generating plant. Although its structure is similar to that of induction motors, its reactive power control is more ... Keywords: doubly fed induction generator, genetic algorithms, optimal reactive power planning, optimization

P. Sangsarawut; A. Oonsivilai; T. Kulworawanichpong

2010-03-01T23:59:59.000Z

225

Optimal reactive power planning of doubly fed induction generators using genetic algorithms  

Science Conference Proceedings (OSTI)

This paper describes optimal reactive power control of a doubly fed induction generator (DFIG), which is widely used in a distributed generating plant. Although its structure is similar to that of an induction motor, its reactive power control is more ... Keywords: doubly fed induction generator, genetic algorithms, optimal reactive power planning, optimization

P. Sangsarawut; A. Oonsivilai; T. Kulworawanichpong

2010-02-01T23:59:59.000Z

226

Optimal Reactive Power Planning of Radial Distribution Systems with Distributed Generation  

Science Conference Proceedings (OSTI)

The paper analyzes reactive power optimization problem in distribution system with wind power and PV generators. Reactive power optimization mathematical model including the active power loss, reactive power compensation capacity and static voltage margin ... Keywords: Distributed generation, Distributed Generation, Immune Algorithm, Cluster Evolutionary

Li Shengqi, Zeng Lilin, Li Yongan, He Zhengping

2013-01-01T23:59:59.000Z

227

Assessment of the Economic Potential of Microgrids for Reactive Power Supply  

E-Print Network (OSTI)

Assessment of the Economic Potential of Microgrids for Reactive Power Supply Jan von Appen1 , Chris. This paper outlines the economic potential of DERs coordinated in a microgrid to provide reactive power possibilities of creating an incentive for microgrids to provide reactive power. Index Terms ­ microgrids

228

Reactive Distillation for Esterification of Bio-based Organic Acids  

DOE Green Energy (OSTI)

The following is the final report of the three year research program to convert organic acids to their ethyl esters using reactive distillation. This report details the complete technical activities of research completed at Michigan State University for the period of October 1, 2003 to September 30, 2006, covering both reactive distillation research and development and the underlying thermodynamic and kinetic data required for successful and rigorous design of reactive distillation esterification processes. Specifically, this project has led to the development of economical, technically viable processes for ethyl lactate, triethyl citrate and diethyl succinate production, and on a larger scale has added to the overall body of knowledge on applying fermentation based organic acids as platform chemicals in the emerging biorefinery. Organic acid esters constitute an attractive class of biorenewable chemicals that are made from corn or other renewable biomass carbohydrate feedstocks and replace analogous petroleum-based compounds, thus lessening U.S. dependence on foreign petroleum and enhancing overall biorefinery viability through production of value-added chemicals in parallel with biofuels production. Further, many of these ester products are candidates for fuel (particularly biodiesel) components, and thus will serve dual roles as both industrial chemicals and fuel enhancers in the emerging bioeconomy. The technical report from MSU is organized around the ethyl esters of four important biorenewables-based acids: lactic acid, citric acid, succinic acid, and propionic acid. Literature background on esterification and reactive distillation has been provided in Section One. Work on lactic acid is covered in Sections Two through Five, citric acid esterification in Sections Six and Seven, succinic acid in Section Eight, and propionic acid in Section Nine. Section Ten covers modeling of ester and organic acid vapor pressure properties using the SPEAD (Step Potential Equilibrium and Dynamics) method.

Fields, Nathan; Miller, Dennis J.; Asthana, Navinchandra S.; Kolah, Aspi K.; Vu, Dung; Lira, Carl T.

2008-09-23T23:59:59.000Z

229

Dynamics of inelastic and reactive gas-surface collisions  

DOE Green Energy (OSTI)

The dynamics of inelastic and reactive collisions in atomic beam-surface scattering are presented. The inelastic scattering of hyperthermal rare gaseous atoms from three alkali halide surfaces (LiF, NaCl, GI)was studied to understand mechanical energy transfer in unreactive systems. The dynamics of the chemical reaction in the scattering of H(D) atoms from the surfaces of LIF(001) and the basal plane of graphite were also studied.

Smoliar, L.A.

1995-04-01T23:59:59.000Z

230

Options for Control of Reactive Power by Distributed Photovoltaic Generators  

E-Print Network (OSTI)

High penetration levels of distributed photovoltaic(PV) generation on an electrical distribution circuit present several challenges and opportunities for distribution utilities. Rapidly varying irradiance conditions may cause voltage sags and swells that cannot be compensated by slowly responding utility equipment resulting in a degradation of power quality. Although not permitted under current standards for interconnection of distributed generation, fast-reacting, VAR-capable PV inverters may provide the necessary reactive power injection or consumption to maintain voltage regulation under difficult transient conditions. As side benefit, the control of reactive power injection at each PV inverter provides an opportunity and a new tool for distribution utilities to optimize the performance of distribution circuits, e.g. by minimizing thermal losses. We discuss and compare via simulation various design options for control systems to manage the reactive power generated by these inverters. An important design decision that weighs on the speed and quality of communication required is whether the control should be centralized or distributed (i.e. local). In general, we find that local control schemes are capable for maintaining voltage within acceptable bounds. We consider the benefits of choosing different local variables on which to control and how the control system can be continuously tuned between robust voltage control, suitable for daytime operation when circuit conditions can change rapidly, and loss minimization better suited for nighttime operation.

Petr Sulc; Konstantin Turitsyn; Scott Backhaus; Michael Chertkov

2010-08-04T23:59:59.000Z

231

Conversion of carboxylate salts to carboxylic acids via reactive distillation  

E-Print Network (OSTI)

The purpose of this study is to convert carboxylate salts (e.g. calcium acetate, propionate, and butyrate) into carboxylic acids (e.g., acetic, propionic, and butyric acids). The carboxylate salts can be produced from wastes, such as paper fines, municipal solid wastes, sewage sludge, and industrial biosludge. Using a proprietary technology owned by Texas A&M University the wastes are first treated with lime to enhance reactivity. Then they are converted to calcium carboxylate salts using a mixed culture of microorganisms derived from cattle rumen or anaerobic waste treatment facilities. The paper fines and municipal solid waste provide energy, whereas the industrial biosludge and sewage sludge provide nutrients for the microorganisms. The calcium carboxylate salts are concentrated and reacted with a low-molecular-weight tertiary amine and carbon dioxide to precipitate calcium carbonate. In a distillation column, the low-molecular-weight amine carboxylate reacts with a high-molecular-weight tertiary amine allowing the low-molecular-weight amine to be recovered from the top of the column. The resulting high-molecular-weight amine carboxylate is converted to amine and carboxylic acid in a reactive distillation column. This project focuses on the conversion of the carboxylate salts produced via fermentation into their corresponding acids via reactive distillation. The primary objective is to determine the optimal operating conditions of the distillation. A secondary objective is to optimize the precipitation step in the recovery process.

Williamson, Shelly Ann

2000-01-01T23:59:59.000Z

232

Dynamic Reactive Power Control of Isolated Power Systems  

E-Print Network (OSTI)

This dissertation presents dynamic reactive power control of isolated power systems. Isolated systems include MicroGrids in islanded mode, shipboard power systems operating offshore, or any other power system operating in islanded mode intentionally or due to a fault. Isolated power systems experience fast transients due to lack of an infinite bus capable of dictating the voltage and frequency reference. This dissertation only focuses on reactive control of islanded MicroGrids and AC/DC shipboard power systems. The problem is tackled using a Model Predictive Control (MPC) method, which uses a simplified model of the system to predict the voltage behavior of the system in future. The MPC method minimizes the voltage deviation of the predicted bus voltage; therefore, it is inherently robust and stable. In other words, this method can easily predict the behavior of the system and take necessary control actions to avoid instability. Further, this method is capable of reaching a smooth voltage profile and rejecting possible disturbances in the system. The studied MicroGrids in this dissertation integrate intermittent distributed energy resources such as wind and solar generators. These non-dispatchable sources add to the uncertainty of the system and make voltage and reactive control more challenging. The model predictive controller uses the capability of these sources and coordinates them dynamically to achieve the voltage goals of the controller. The MPC controller is implemented online in a closed control loop, which means it is self-correcting with the feedback it receives from the system.

Falahi, Milad

2012-12-01T23:59:59.000Z

233

Application of molten salts in pyrochemical processing of reactive metals  

Science Conference Proceedings (OSTI)

Various mixes of chloride and fluoride salts are used as the media for conducting pyrochemical processes in the production and purification of reactive metals. These processes generate a significant amount of contaminated waste that has to be treated for recycling or disposal. Molten calcium chloride based salt systems have been used in this work to electrolytically regenerate calcium metal from calcium oxide for the in situ reduction of reactive metal oxides. The recovery of calcium is characterized by the process efficiency to overcome back reactions in the electrowinning cell. A thermodynamic analysis, based on fundamental rate theory, has been performed to understand the process parameters controlling the metal deposition, rate, behavior of the ceramic anode-sheath and influence of the back-reactions. It has been observed that the deposition of calcium is dependent on the ionic diffusion through the sheath. It has also been evidenced that the recovered calcium is completely lost through the back-reactions in the absence of a sheath. A practical scenario has also been presented where the electrowon metal can be used in situ as a reductant to reduce another reactive metal oxide.

Mishra, B.; Olson, D.L. (Colorado School of Mines, Golden, CO (United States). Kroll Inst. for Extractive Metallurgy); Averill, W.A. (EG and G Rocky Flats, Inc., Golden, CO (United States). Rocky Flats Plant)

1992-01-01T23:59:59.000Z

234

A comparison of results obtained with two subsurface non-isothermal multiphase reactive transport simulators, FADES-CORE and TOUGHREACT  

E-Print Network (OSTI)

saturated porous media with multiphase flow. FADES-CORE hasisothermal multiphase flow with reactive transport in porousmultiphase flow with multicomponent reactive transport in porous

Juncosa Rivera, Ricardo; Xu, Tianfu; Pruess, Karsten

2001-01-01T23:59:59.000Z

235

Fluid-rock interaction: A reactive transport approach  

SciTech Connect

Fluid-rock interaction (or water-rock interaction, as it was more commonly known) is a subject that has evolved considerably in its scope over the years. Initially its focus was primarily on interactions between subsurface fluids of various temperatures and mostly crystalline rocks, but the scope has broadened now to include fluid interaction with all forms of subsurface materials, whether they are unconsolidated or crystalline ('fluid-solid interaction' is perhaps less euphonious). Disciplines that previously carried their own distinct names, for example, basin diagenesis, early diagenesis, metamorphic petrology, reactive contaminant transport, chemical weathering, are now considered to fall under the broader rubric of fluid-rock interaction, although certainly some of the key research questions differ depending on the environment considered. Beyond the broadening of the environments considered in the study of fluid-rock interaction, the discipline has evolved in perhaps an even more important way. The study of water-rock interaction began by focusing on geochemical interactions in the absence of transport processes, although a few notable exceptions exist (Thompson 1959; Weare et al. 1976). Moreover, these analyses began by adopting a primarily thermodynamic approach, with the implicit or explicit assumption of equilibrium between the fluid and rock. As a result, these early models were fundamentally static rather than dynamic in nature. This all changed with the seminal papers by Helgeson and his co-workers (Helgeson 1968; Helgeson et al. 1969) wherein the concept of an irreversible reaction path was formally introduced into the geochemical literature. In addition to treating the reaction network as a dynamically evolving system, the Helgeson studies introduced an approach that allowed for the consideration of a multicomponent geochemical system, with multiple minerals and species appearing as both reactants and products, at least one of which could be irreversible. Helgeson's pioneering approach was given a more formal kinetic basis (including the introduction of real time rather than reaction progress as the independent variable) in subsequent studies (Lasaga 1981; Aagaard and Helgeson 1982; Lasaga 1984). The reaction path approach can be used to describe chemical processes in a batch or closed system (e.g., a laboratory beaker), but such systems are of limited interest in the Earth sciences where the driving force for most reactions is transport. Lichtner (1988) clarified the application of the reaction path models to water-rock interaction involving transport by demonstrating that they could be used to describe pure advective transport through porous media. By adopting a reference frame which followed the fluid packet as it moved through the medium, the reaction progress variable could be thought of as travel time instead. Multi-component reactive transport models that could treat any combination of transport and biogeochemical processes date back to the early 1980s. Berner and his students applied continuum reactive transport models to describe processes taking place during the early diagenesis of marine sediments (Berner 1980). Lichtner (1985) outlined much of the basic theory for a continuum model for multicomponent reactive transport. Yeh and Tripathi (1989) also presented the theoretical and numerical basis for the treatment of reactive contaminant transport. Steefel and Lasaga (1994) presented a reactive flow and transport model for nonisothermal, kinetically-controlled water-rock interaction and fracture sealing in hydrothermal systems based on simultaneous numerical solution of both reaction and transport This chapter begins with a review of the important transport processes that affect or even control fluid-rock interaction. This is followed by a general introduction to the governing equations for reactive transport, which are broadly applicable to both qualitative and quantitative interpretations of fluid-rock interactions. This framework is expanded through a discussion of specific topics that are the f

Steefel, C.; Maher, K.

2009-04-01T23:59:59.000Z

236

Performance of a Permeable Reactive Barrier Using Granular Zero-Valent  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Performance of a Permeable Reactive Barrier Using Granular Performance of a Permeable Reactive Barrier Using Granular Zero-Valent Iron: FY 2004 Annual Report Durango, Colorado, Disposal Site Performance of a Permeable Reactive Barrier Using Granular Zero-Valent Iron: FY 2004 Annual Report Durango, Colorado, Disposal Site Performance of a Permeable Reactive Barrier Using Granular Zero-Valent Iron: FY 2004 Annual Report Durango, Colorado, Disposal Site Performance of a Permeable Reactive Barrier Using Granular Zero-Valent Iron: FY 2004 Annual Report Durango, Colorado, Disposal Site More Documents & Publications Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing Final Report Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing

237

ITER Model Coil Tests Overview: Nb3Sn Strand Properties in Cable-in-Conduit-Conductors  

SciTech Connect

During the ITER Model Coil Program two large coils and three Insert coils were built and tested. The test campaigns provided very valuable data on the Conductor in Conduit Cable (CICC) properties. The tests showed that the Nb3Sn strands in CICC behave differently than so-called witness strands, which underwent the same heat treatment. The paper describes Volt-temperature characteristics (VTC) and Volt-Ampere characteristics (VAC) measured in the tests, presents comparisons with the witness strands, and interprets the test results.

Martovetsky, N N

2003-04-14T23:59:59.000Z

238

Reactive dynamics of inertial particles in nonhyperbolic chaotic flows  

E-Print Network (OSTI)

Anomalous kinetics of infective (e.g., autocatalytic) reactions in open, nonhyperbolic chaotic flows are important for many applications in biological, chemical, and environmental sciences. We present a scaling theory for the singular enhancement of the production caused by the universal, underlying fractal patterns. The key dynamical invariant quantities are the effective fractal dimension and effective escape rate, which are primarily determined by the hyperbolic components of the underlying dynamical invariant sets. The theory is general as it includes all previously studied hyperbolic reactive dynamics as a special case. We introduce a class of dissipative embedding maps for numerical verification.

Adilson E. Motter; Ying-Cheng Lai; Celso Grebogi

2003-11-26T23:59:59.000Z

239

Reactive multilayer synthesis of hard ceramic foils and films  

DOE Patents (OSTI)

Disclosed is method for synthesizing hard ceramic materials such as carbides, borides and aluminides, particularly in the form of coatings provided on another material so as to improve the wear and abrasion performance of machine tools, for example. Method involves the sputter deposition of alternating layers of reactive metals with layers of carbon, boron, or aluminum and the subsequent reaction of the multilayered structure to produce a dense crystalline ceramic. The material can be coated on a substrate or formed as a foil which can be coiled as a tape for later use.

Makowiecki, D.M.; Holt, J.B.

1993-12-31T23:59:59.000Z

240

Reactive sticking coefficients for silane and disilane on polycrystalline silicon  

SciTech Connect

Reactive sticking coefficients (RSCs) were measured for silane and disilane on polycrystalline silicon for a wide range of temperature and flux (pressure) conditions. The data were obtained from deposition-rate measurements using molecular beam scattering and a very low-pressure cold-wall reactor. The RSCs have nonlinear Arrhenius temperature dependencies and decrease with increasing flux at low (710 /sup 0/C) temperatures. Several simple models are proposed to explain these observations. The results are compared with previous studies of the SiH/sub 4//Si(s) reaction and low-pressure chemical vapor deposition-rate measurements.

Buss, R.J.; Ho, P.; Breiland, W.G.; Coltrin, M.E.

1988-04-15T23:59:59.000Z

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Voltage control scheme in distribution network with double feed induction generator wind farm  

Science Conference Proceedings (OSTI)

This paper presents the particle swarm optimization (PSO) for reactive power and voltage control (Volt/Var Control) in distribution system considering DFIG wind farm. In this paper, the reactive power output of DFIG wind farm has been considered as the ... Keywords: DFIG wind turbine, Volt/Var control, distribution network, optimization, particle swarm, wind farm

Jingjing Zhao; Xin Li; Jutao Hao

2009-08-01T23:59:59.000Z

242

Evaluation of a new type stable nickel-zinc battery for electric vehicle application. Final report  

SciTech Connect

This report describes discharge-recharge cycle testing of 14 nickel-zinc storage battery cells of a proprietary design. This testing was to obtain performance data on new types of stabilized nickel-zinc battery cells for possible electric vehicle applications. The test sample cells were manufactured by Electrochimica Corporation (ELCA) in two sizes (15 ampere-hours and 225 ampere-hours) with a total of seven different internal combinations. The cells completed up to 470 cycles when testing was halted due to funding limitations. Near the end of testing, the cells were providing 40% of nominal capacity when discharged to 1.2 volts and 58 to 73% when discharged in two steps to 1.0 volt.

Not Available

1985-07-26T23:59:59.000Z

243

Evaluating advanced LMR (liquid metal reactor) reactivity feedbacks using SSC  

Science Conference Proceedings (OSTI)

Analyses of the PRISM and SAFR Liquid Metal Reactors with SSC are discussed from a safety and licensing perspective. The PRISM and SAFR reactors with metal fuel are designed for inherent shutdown responses to loss-of-flow and loss-of-heat-sink events. The demonstration of this technology was performed by EBR-II during experiments in April 1986 by ANL (Planchon, et al.). Response to postulated TOPs (control rod withdrawal) are made acceptable largely by reducing reactivity swings, and therefore minimizing the size of possible ractivity insertions. Analyses by DOE and the contractors GE, RI, and ANL take credit for several reactivity feedback mechanisms during transient calculations. These feedbacks include Doppler, sodium density, and thermal expansion of the grid plates, the load pads, the fuel (axial) and the control rod which are now factored into the BNL SSC analyses. The bowing feedback mechanism is not presently modeled in the SSC due to its complexity and subsequent large uncertainty. The analysis is conservative by not taking credit for this negative feedback mechanism. Comparisons of BNL predictions with DOE contractors are provided.

Slovik, G.C.; Van Tuyle, G.J.; Kennett, R.J.; Cheng, H.S.

1988-01-01T23:59:59.000Z

244

Optimization of reactive distillation processes with simulated annealing  

E-Print Network (OSTI)

A simulated annealing-based algorithm (MSIMPSA) suitable for the optimization of mixed integer non-linear programming (MINLP) problems was applied to the synthesis of a non-equilibrium reactive distillation column. A simulation model based on an extension of conventional distillation is proposed for the simulation step of the optimization problem. In the case of ideal vapor}liquid equilibrium, the simulation results are similar to those obtained by Ciric and Gu (1994, AIChE Journal, 40(9), 1479) using the GAMS environment and to those obtained with the AspenPlus modular simulator. The optimization results are also similar to those previously reported and similar to those using an adaptive random search algorithm (MSGA). The optimizations were also performed with non-ideal vapor}liquid equilibrium, considering either distributed feed and reaction trays or single feed and reaction tray. The results show that the optimized objective function values are very similar, and mostly independent of the number of trays and of the reaction distribution. It is shown that the proposed simulation/optimization equation-oriented environments are capable of providing optimized solutions which are close to the global optimum, and reveal its adequacy for the optimization of reactive distillation

M. F. Cardoso; R. L. Salcedo; S. Feyo De Azevedo; D. Barbosa

1999-01-01T23:59:59.000Z

245

Hybrid nuclear reactor grey rod to obtain required reactivity worth  

DOE Patents (OSTI)

Hybrid nuclear reactor grey rods are described, wherein geometric combinations of relatively weak neutron absorber materials such as stainless steel, zirconium or INCONEL, and relatively strong neutron absorber materials, such as hafnium, silver-indium cadmium and boron carbide, are used to obtain the reactivity worths required to reach zero boron change load follow. One embodiment includes a grey rod which has combinations of weak and strong neutron absorber pellets in a stainless steel cladding. The respective pellets can be of differing heights. A second embodiment includes a grey rod with a relatively thick stainless steel cladding receiving relatively strong neutron absorber pellets only. A third embodiment includes annular relatively weak netron absorber pellets with a smaller diameter pellet of relatively strong absorber material contained within the aperture of each relatively weak absorber pellet. The fourth embodiment includes pellets made of a homogeneous alloy of hafnium and a relatively weak absorber material, with the percentage of hafnium chosen to obtain the desired reactivity worth.

Miller, John V. (Munhall, PA); Carlson, William R. (Scott Township, Allegheny County, PA); Yarbrough, Michael B. (Hempfield Township, Westmoreland County, PA)

1991-01-01T23:59:59.000Z

246

Coordination of reactive power scheduling in a multi-area power system operated by independent utilities.  

E-Print Network (OSTI)

??This thesis addresses the problem of reactive power scheduling in a power system with several areas controlled by independent transmission system operators (TSOs). To design… (more)

Phulpin, Yannick

247

Assessment of the Economic Potential of Microgrids for Reactive Power Supply  

E-Print Network (OSTI)

Group, October 2010. [7] Microgrid Symposiums, Berkeley (compensation ranges from a microgrid cost perspective forsystem wide impacts of microgrid participation in reactive

Appen, Jan von

2012-01-01T23:59:59.000Z

248

Simulations of Deflagration-to-Detonation Transition in Reactive Gases |  

NLE Websites -- All DOE Office Websites (Extended Search)

numerically generated pseudo-schlieren image numerically generated pseudo-schlieren image Weak ignition behind a reflected Mach=1.5 shock in a stoichiometric hydrogen-oxygen mixture at 0.1 atm initial pressure. Picture shows a numerically generated pseudo-schlieren image of the onset of a detonation in a turbulent boundary layer. Alexei Khokhlov, University of Chicago; Charles Bacon, Argonne National Laboratory, Joanna Austin, Andrew Knisely, University of Illinois at Urbanna-Champaign Simulations of Deflagration-to-Detonation Transition in Reactive Gases PI Name: Alexei Khokhlov PI Email: ajk@oddjob.uchicago.edu Institution: The University of Chicago Allocation Program: INCITE Allocation Hours at ALCF: 130 Million Year: 2013 Research Domain: Chemistry Hydrogen is an abundant, environmentally friendly fuel with the potential

249

Reactive gas atomization processing for Fe-based ODS alloys  

Science Conference Proceedings (OSTI)

Gas atomization reaction synthesis was employed as a simplified method for processing oxide dispersion forming precursor Fe-based powders (e.g., Fe-Cr-Y-Hf). During this process a reactive atomization gas (i.e., Ar-O{sub 2}) was used to oxidize the powder surfaces during primary break-up and rapid solidification of the molten alloy. This resulted in envelopment of the powders by an ultra-thin (t dispersion strengthened microstructures were engineered from different powder particle size ranges, illustrating microstructural control as a function of particle solidification rate. Additionally, preliminary thermal-mechanical processing was used to develop a fine scale dislocation substructure for ultimate strengthening of the alloy.

Rieken, J.R.; Anderson, I.E.; Kramer, M.J.; Odette, G.R.; Stergarc, E.; Haney, E.

2011-08-08T23:59:59.000Z

250

Distributed control for optimal reactive power compensation in smart microgrids  

E-Print Network (OSTI)

We consider the problem of optimal reactive power compensation for the minimization of power distribution losses in a smart microgrid. We first propose an approximate model for the power distribution network, which allows us to cast the problem into the class of convex quadratic, linearly constrained, optimization problems. We also show how this model provides the tools for a distributed approach, in which agents have a partial knowledge of the problem parameters and state, and can only perform local measurements. Then, we design a randomized, gossip-like optimization algorithm, providing conditions for convergence together with an analytic characterization of the convergence speed. The analysis shows that the best performance can be achieved when we command cooperation among agents that are neighbors in the smart microgrid topology. Numerical simulations are included to validate the proposed model and to confirm the analytic results about the performance of the proposed algorithm.

Bolognani, Saverio

2011-01-01T23:59:59.000Z

251

REACTIVITY OF RESORCINOL FORMALDEHYDE RESIN WITH NITRIC ACID  

Science Conference Proceedings (OSTI)

Solid-state infrared spectroscopy, differential scanning calorimetry, and elemental analysis have been used to evaluate the reactivity of resorcinol formaldehyde resin with nitric acid and characterize the solid product. Two distinct reactions were identified within the temperature range 25-55 C. The first reaction is primarily associated with resin nitration, while the second involves bulk oxidation and degradation of the polymer network leading to dissolution and off-gassing. Reaction was confirmed with nitric acid concentrations as low as 3 M at 25 C applied temperature and 0.625 M at 66 C. Although a nitrated resin product can be isolated under appropriate experimental conditions, calorimetry testing indicates no significant hazard associated with handling the dry material.

King, W; Fernando Fondeur, F; Bill Wilmarth, B; Myra Pettis, M; Shirley Mccollum, S

2006-06-14T23:59:59.000Z

252

Anode reactive bleed and injector shift control strategy  

DOE Patents (OSTI)

A system and method for correcting a large fuel cell voltage spread for a split sub-stack fuel cell system. The system includes a hydrogen source that provides hydrogen to each split sub-stack and bleed valves for bleeding the anode side of the sub-stacks. The system also includes a voltage measuring device for measuring the voltage of each cell in the split sub-stacks. The system provides two levels for correcting a large stack voltage spread problem. The first level includes sending fresh hydrogen to the weak sub-stack well before a normal reactive bleed would occur, and the second level includes sending fresh hydrogen to the weak sub-stack and opening the bleed valve of the other sub-stack when the cell voltage spread is close to stack failure.

Cai, Jun [Rochester, NY; Chowdhury, Akbar [Pittsford, NY; Lerner, Seth E [Honeoye Falls, NY; Marley, William S [Rush, NY; Savage, David R [Rochester, NY; Leary, James K [Rochester, NY

2012-01-03T23:59:59.000Z

253

Transparent electrical conducting films by activated reactive evaporation  

DOE Patents (OSTI)

Process and apparatus for producing transparent electrical conducting thin films by activated reactive evaporation is disclosed. Thin films of low melting point metals and alloys, such as indium oxide and indium oxide doped with tin, are produced by physical vapor deposition. The metal or alloy is vaporized by electrical resistance heating in a vacuum chamber, oxygen and an inert gas such as argon are introduced into the chamber, and vapor and gas are ionized by a beam of low energy electrons in a reaction zone between the resistance heater and the substrate. There is a reaction between the ionized oxygen and the metal vapor resulting in the metal oxide which deposits on the substrate as a thin film which is ready for use without requiring post deposition heat treatment. 1 fig.

Bunshah, R.; Nath, P.

1982-06-22T23:59:59.000Z

254

Transparent electrical conducting films by activated reactive evaporation  

DOE Patents (OSTI)

Process and apparatus for producing transparent electrical conducting thin films by activated reactive evaporation. Thin films of low melting point metals and alloys, such as indium oxide and indium oxide doped with tin, are produced by physical vapor deposition. The metal or alloy is vaporized by electrical resistance heating in a vacuum chamber, oxygen and an inert gas such as argon are introduced into the chamber, and vapor and gas are ionized by a beam of low energy electrons in a reaction zone between the resistance heater and the substrate. There is a reaction between the ionized oxygen and the metal vapor resulting in the metal oxide which deposits on the substrate as a thin film which is ready for use without requiring post deposition heat treatment.

Bunshah, Rointan (Los Angeles, CA); Nath, Prem (Troy, MI)

1982-01-01T23:59:59.000Z

255

Advanced hydraulic fracturing methods to create in situ reactive barriers  

Science Conference Proceedings (OSTI)

This article describes the use of hydraulic fracturing to increase permeability in geologic formations where in-situ remedial action of contaminant plumes will be performed. Several in-situ treatment strategies are discussed including the use of hydraulic fracturing to create in situ redox zones for treatment of organics and inorganics. Hydraulic fracturing methods offer a mechanism for the in-situ treatment of gently dipping layers of reactive compounds. Specialized methods using real-time monitoring and a high-energy jet during fracturing allow the form of the fracture to be influenced, such as creation of assymmetric fractures beneath potential sources (i.e. tanks, pits, buildings) that should not be penetrated by boring. Some examples of field applications of this technique such as creating fractures filled with zero-valent iron to reductively dechlorinate halogenated hydrocarbons, and the use of granular activated carbon to adsorb compounds are discussed.

Murdoch, L. [FRX Inc., Cincinnati, OH (United States)]|[Clemson Univ., SC (United States). Dept. of Geological Sciences; Siegrist, B.; Meiggs, T. [Oak Ridge National Lab., TN (United States)] [and others

1997-12-31T23:59:59.000Z

256

Sensitivity and uncertainty analysis applied to the JHR reactivity prediction  

SciTech Connect

The on-going AMMON program in EOLE reactor at CEA Cadarache (France) provides experimental results to qualify the HORUS-3D/N neutronics calculation scheme used for the design and safety studies of the new Material Testing Jules Horowitz Reactor (JHR). This paper presents the determination of technological and nuclear data uncertainties on the core reactivity and the propagation of the latter from the AMMON experiment to JHR. The technological uncertainty propagation was performed with a direct perturbation methodology using the 3D French stochastic code TRIPOLI4 and a statistical methodology using the 2D French deterministic code APOLLO2-MOC which leads to a value of 289 pcm (1{sigma}). The Nuclear Data uncertainty propagation relies on a sensitivity study on the main isotopes and the use of a retroactive marginalization method applied to the JEFF 3.1.1 {sup 27}Al evaluation in order to obtain a realistic multi-group covariance matrix associated with the considered evaluation. This nuclear data uncertainty propagation leads to a K{sub eff} uncertainty of 624 pcm for the JHR core and 684 pcm for the AMMON reference configuration core. Finally, transposition and reduction of the prior uncertainty were made using the Representativity method which demonstrates the similarity of the AMMON experiment with JHR (the representativity factor is 0.95). The final impact of JEFF 3.1.1 nuclear data on the Begin Of Life (BOL) JHR reactivity calculated by the HORUS-3D/N V4.0 is a bias of +216 pcm with an associated posterior uncertainty of 304 pcm (1{sigma}). (authors)

Leray, O.; Vaglio-Gaudard, C.; Hudelot, J. P.; Santamarina, A.; Noguere, G. [CEA, DER, SPRC, F-13108 St Paul-Lez-Durance (France); Di-Salvo, J. [CEA, DER, SPEx, F-13108 St Paul-Lez-Durance (France)

2012-07-01T23:59:59.000Z

257

Modeling of concentrated aqueous solutions: Efficient implementation of Pitzer equations in geochemical and reactive transport models  

Science Conference Proceedings (OSTI)

Modeling concentrated solutions demands the use of ion-interaction models such as Pitzer equations, which involve a large number of operations. Implementation of these models in large reactive transport simulations significantly increases the computation ... Keywords: Concentrated solutions, Evaporation of seawater, Geochemical modeling, HMW model, Invariant points, Object-oriented programming, Pitzer, Reactive transport modeling

S. A. Bea; J. Carrera; C. Ayora; F. Batlle

2010-04-01T23:59:59.000Z

258

Reactive transport model for the ambient unsaturated hydrogeochemical system at Yucca mountain, Nevada  

Science Conference Proceedings (OSTI)

To assist a technical review of a potential application for a geologic repository, a reactive transport model is presented for the ambient hydrogeochemical system at Yucca Mountain (YM). The model simulates two-phase, nonisothermal, advective and diffusive ... Keywords: Yucca mountain, geochemistry, groundwater chemistry, groundwater flow and transport, hydrology, reactive transport model, unsaturated zone

Lauren Browning; William M. Murphy; Chandrika Manepally; Randall Fedors

2003-04-01T23:59:59.000Z

259

Reactive transport in aquatic ecosystems: Rapid model prototyping in the open source software R  

Science Conference Proceedings (OSTI)

The concentrations of many natural compounds are altered by chemical and biological transformations, and physical processes such as adsorption and transport. Their fate can be predicted using reactive transport models that describe reaction and advective ... Keywords: Model, Open source, R, Reactive transport, Software

Karline Soetaert; Filip Meysman

2012-06-01T23:59:59.000Z

260

Cost of Providing Ancillary Services from Power Plants: Reactive Supply and Voltage Control  

Science Conference Proceedings (OSTI)

This report provides a methodology for determining the variable costs of generating and supplying reactive power to a transmission system, via the generator step-up transformer, for system voltage control. The report examines the costs of additional energy losses, maintenance, repair, and plant aging associated with the generation of reactive power. TR-107270-V3SI contains System of International units.

1997-09-02T23:59:59.000Z

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Multi-objective reactive power market clearing in competitive electricity market using HFMOEA  

Science Conference Proceedings (OSTI)

This paper presents an application of a hybrid fuzzy multi-objective evolutionary algorithm (HFMOEA) for solving a highly constraint, mixed integer type, complex multi-objective reactive power market clearing (RPMC) problem for the competitive electricity ... Keywords: Competitive electricity market, Fuzzy logic controller, Hybrid evolutionary algorithm, Multi-objective optimization, Pareto-optimal front, Reactive power market clearing

Ashish Saini; Amit Saraswat

2013-04-01T23:59:59.000Z

262

A transport based one-dimensional perturbation code for reactivity calculations in metal systems  

SciTech Connect

A one-dimensional reactivity calculation code is developed using first order perturbation theory. The reactivity equation is based on the multi-group transport equation using the discrete ordinates method for angular dependence. In addition to the first order perturbation approximations, the reactivity code uses only the isotropic scattering data, but cross section libraries with higher order scattering data can still be used with this code. The reactivity code obtains all the flux, cross section, and geometry data from the standard interface files created by ONEDANT, a discrete ordinates transport code. Comparisons between calculated and experimental reactivities were done with the central reactivity worth data for Lady Godiva, a bare uranium metal assembly. Good agreement is found for isotopes that do not violate the assumptions in the first order approximation. In general for cases where there are large discrepancies, the discretized cross section data is not accurately representing certain resonance regions that coincide with dominant flux groups in the Godiva assembly. Comparing reactivities calculated with first order perturbation theory and a straight {Delta}k/k calculation shows agreement within 10% indicating the perturbation of the calculated fluxes is small enough for first order perturbation theory to be applicable in the modeled system. Computation time comparisons between reactivities calculated with first order perturbation theory and straight {Delta}k/k calculations indicate considerable time can be saved performing a calculation with a perturbation code particularly as the complexity of the modeled problems increase.

Wenz, T.R.

1995-02-01T23:59:59.000Z

263

Benchmarking a Visual-Basic based multi-component one-dimensional reactive transport modeling tool  

Science Conference Proceedings (OSTI)

We present the details of a comprehensive numerical modeling tool, RT1D, which can be used for simulating biochemical and geochemical reactive transport problems. The code can be run within the standard Microsoft EXCEL Visual Basic platform, and it does ... Keywords: Bioremediation, Geochemical transport, Groundwater models, Numerical model, Reactive transport

Jagadish Torlapati; T. Prabhakar Clement

2013-01-01T23:59:59.000Z

264

Optimal Allocation of Reactive Power Source in Wind Farms Using Sensitivity Analysis and Tabu Algorithm  

Science Conference Proceedings (OSTI)

Considering wind farms real operation characteristics, a novel method using sensitivity analysis and Tabu algorithm for reactive power compensation allocations is proposed. In this paper, the sensitivity coefficient is defined as partial derivative of ... Keywords: Wind farm, Sensitivity analysis, Reactive power compensation, SVC, Tabu algorithm

Ping Zhang; XiangJun Zeng; Ling Li

2008-10-01T23:59:59.000Z

265

Reactive and Real-Time Systems Course: How to Get the Most Out of it  

Science Conference Proceedings (OSTI)

The paper describes the syllabus and the students’ projects from a graduate course on the subject of “Reactive and Real-Time Systems”, taught at Tel-Aviv University and at the Open University of Israel. The course focuses on the development ... Keywords: course syllabus, reactive real-time systems, scheduling, synchronous languages, verification

Tal Lev-Ami; Shmuel S. Tyszberowicz

2003-09-01T23:59:59.000Z

266

PEV-based Reactive Power Compensation for Wind DG Units: A Stackelberg Game Approach  

E-Print Network (OSTI)

turbine's inductive load to ensure a stable voltage profile in the system. Since reactive power can only from the load centers, DG units will speed up the revolution of providing power on site with little unit. Reactive power compensa- tion is needed since the load is not pure resistive and may include

Wu, Chenye

267

Accelerating moderately stiff chemical kinetics in reactive-flow simulations using GPUs  

Science Conference Proceedings (OSTI)

The chemical kinetics ODEs arising from operator-split reactive-flow simulations were solved on GPUs using explicit integration algorithms. Nonstiff chemical kinetics of a hydrogen oxidation mechanism (9 species and 38 irreversible reactions) were computed ... Keywords: CUDA, Chemical kinetics, GPU, Reactive-flow modeling, Stiff chemistry

Kyle E. Niemeyer, Chih-Jen Sung

2014-01-01T23:59:59.000Z

268

Joint optimization algorithm for network reconfiguration and reactive power control of wind farm in distribution system  

Science Conference Proceedings (OSTI)

In recent years, the number of small size wind farms used as DG sources located within the distribution system are rapidly increasing. Wind farm made up with doubly fed induction generators (DFIG) is proposed in this paper as the continuous reactive ... Keywords: DFIG wind turbine, network reconfiguration, particle swarm optimization, reactive power control, wind farm

Jingjing Zhao; Xin Li; Jiping Lu; Congli Zhang

2009-02-01T23:59:59.000Z

269

Lessons learned from reactive transport modeling of a low-activity waste glass disposal system  

Science Conference Proceedings (OSTI)

A set of reactive chemical transport calculations were conducted with the Subsurface Transport Over Reactive Multiphases (STORM) code to evaluate the long-term performance of a representative low-activity waste glass in a shallow subsurface disposal ... Keywords: chemical transport, low-level waste, numerical model, unsaturated flow, vadose zone

Diana H. Bacon; B. Peter McGrail

2003-04-01T23:59:59.000Z

270

Modeling of Hydrogen Storage Materials: A Reactive Force Field for NaH  

E-Print Network (OSTI)

is the fall in potential energy surface during heating. Keywords: hydrogen storage, reactive force fieldModeling of Hydrogen Storage Materials: A Reactive Force Field for NaH Ojwang' J.G.O.*, Rutger van governing hydrogen desorption in NaH. During the abstraction process of surface molecular hydrogen charge

Goddard III, William A.

271

Depletion Reactivity Benchmark for the International Handbook of Evaluated Reactor Physics Benchmark Experiments  

Science Conference Proceedings (OSTI)

The Electric Power Research Institute– (EPRI-) sponsored depletion reactivity benchmarks documented in reports 1022909, Benchmarks for Quantifying Fuel Reactivity Depletion Uncertainty, and 1025203, Utilization of the EPRI Depletion Benchmarks for Burnup Credit Validation, have been translated to an evaluated benchmark for incorporation in the International Handbook of Evaluated Reactor Physics Benchmark Experiments (IRPhE), published by the Organisation for Economic ...

2013-04-10T23:59:59.000Z

272

Optimal Planning of Reactive Power Compensators for Oil Field Distribution Networks  

Science Conference Proceedings (OSTI)

The characteristic behavior of the loads of oil pumps is analyzed. An approach for low-voltage side reactive power compensators of oil field distribution networks is put forward. Based on the supplied loads of transformers, the index of maximum reduction ... Keywords: Genetic Algorithm, distribution network, oil field, reactive power compensation

Wu Xiaomeng; Yan Suli

2009-05-01T23:59:59.000Z

273

Compatibility Analysis on Existing Reactivity Devices in CANDU 6 Reactors for DUPIC Fuel Cycle  

Science Conference Proceedings (OSTI)

The performance of reactivity devices for a Canada deuterium uranium (CANDU) 6 reactor loaded with Direct Use of Spent Pressurized Water Reactor Fuel In CANDU reactors (DUPIC) fuel is assessed. The reactivity devices studied are the zone controller units, the adjuster rods, and the mechanical control absorbers. For the zone controller system, the bulk reactivity control, spatial power control, and damping capability for spatial oscillation are investigated. For the adjusters, the xenon override, restart after a poison-out, shim operation, and power step-back capabilities are confirmed. The mechanical control absorber is assessed for the function of compensating temperature reactivity feedback following a power reduction. This study shows that the current reactivity device system of a CANDU 6 reactor is compatible with DUPIC fuel for normal and transient operations.

Jeong, Chang-Joon; Choi, Hangbok [Korea Atomic Energy Research Institute (Korea, Republic of)

2000-03-15T23:59:59.000Z

274

Reactivity studies of antitumor active dirhodium compounds with DNA oligonucleotides  

E-Print Network (OSTI)

The study of the mechanism of action of an antitumor active drug is essential for improving the efficacy and reducing the side effects of the drug as well as for developing better alternatives. In this vein, reactions of dirhodium compounds with DNA oligonucleotides were investigated by the techniques of mass spectrometry, HPLC, and NMR spectroscopic analytical methods. The relative reactivities of three dirhodium compounds, namely Rh2(O2CCH3)4, Rh2(O2CCF3)4, and [Rh2(O2CCH3)2(CH3CN)6](BF4)2, with DNA oligonucleotides were studied and compared to the clinically used anticancer drugs cisplatin and carboplatin using both MALDI and ESI mass spectrometric methods. The compound Rh2(O2CCF3)4 exhibits the highest reactivity among the dirhodium compounds, which is comparable to cisplatin, followed by [Rh2(O2CCH3)2(CH3CN)6](BF4)2, and finally Rh2(O2CCH3)4 which is the least reactive. Various dirhodium-oligonucleotide adducts were detected with both MALDI and ESI methods, which involve substitution of different numbers of the original ligands of the given dirhodium compound. ESI MS was found to be a sufficiently soft ionization method for detecting intact metal adducts, and CID MS-MS was useful for detecting weakly bound species such as axial adducts [M+Rh2(O2CCH3)4] and for comparing the relative bond strength between ligands in the metal adduct. A combination of anion exchange HPLC purification and enzymatic digestion studies of the adducts of Rh2(O2CCH3)4 with the 5'-CCTTCAACTCTC oligonucleotide revealed that Rh2(O2CCH3)4 binds to the center or to the ends of the oligonucleotide sequence by displacement of one or two acetate groups. Kinetic products of the type [M+Rh2(O2CCH3)3] obtained from the reaction of Rh2(O2CCH3)4 with 5'-CTCTCAACTTCC were separated by employing both reverse phase and anion exchange HPLC methods. The adduct that involves binding of the dirhodium unit to the exocyclic N4 atom of C5 and the N7 of A6 was found to be most stable whereas other adducts involving binding of C3 or C12 residues are clearly less stable. Reaction of cis-[Rh2(DAP)(O2CCH3)3(CH3OH)](O2CCH3) (DAP = 1,12- diazaperylene) with 5'-CTCTCAACTTCC produced a major adduct in which DAP group intercalates between 6A and 7A in the double stranded adduct with the rhodium atom that is not coordinated to the DAP group forming a covalent bond to the N7 atom of 6A which lends stability to the adduct.

Kang, Mijeong

2005-12-01T23:59:59.000Z

275

Local Dynamic Reactive Power for Correction of System Voltage Problems  

SciTech Connect

Distribution systems are experiencing outages due to a phenomenon known as local voltage collapse. Local voltage collapse is occurring in part because modern air conditioner compressor motors are much more susceptible to stalling during a voltage dip than older motors. These motors can stall in less than 3 cycles (.05s) when a fault, such as on the sub-transmission system, causes voltage to sag to 70 to 60%. The reasons for this susceptibility are discussed in the report. During the local voltage collapse, voltages are depressed for a period of perhaps one or two minutes. There is a concern that these local events are interacting together over larger areas and may present a challenge to system reliability. An effective method of preventing local voltage collapse is the use of voltage regulation from Distributed Energy Resources (DER) that can supply or absorb reactive power. DER, when properly controlled, can provide a rapid correction to voltage dips and prevent motor stall. This report discusses the phenomenon and causes of local voltage collapse as well as the control methodology we have developed to counter voltage sag. The problem is growing because of the use of low inertia, high efficiency air conditioner (A/C) compressor motors and because the use of electric A/C is growing in use and becoming a larger percentage of system load. A method for local dynamic voltage regulation is discussed which uses reactive power injection or absorption from local DER. This method is independent, rapid, and will not interfere with conventional utility system voltage control. The results of simulations of this method are provided. The method has also been tested at the ORNL s Distributed Energy Communications and Control (DECC) Laboratory using our research inverter and synchronous condenser. These systems at the DECC Lab are interconnected to an actual distribution system, the ORNL distribution system, which is fed from TVA s 161kV sub-transmission backbone. The test results are also provided and discussed. The simulations and testing show that local voltage control from DER can prevent local voltage collapse. The results also show that the control can be provided so quickly, within 0.5 seconds, that is does not interfere with conventional utility methods.

Kueck, John D [ORNL; Rizy, D Tom [ORNL; Li, Fangxing [ORNL; Xu, Yan [ORNL; Li, Huijuan [University of Tennessee, Knoxville (UTK); Adhikari, Sarina [ORNL; Irminger, Philip [ORNL

2008-12-01T23:59:59.000Z

276

Advancing Reactive Tracer Methods for Measuring Thermal Evolution in CO2-  

Open Energy Info (EERE)

Advancing Reactive Tracer Methods for Measuring Thermal Evolution in CO2- Advancing Reactive Tracer Methods for Measuring Thermal Evolution in CO2- and Water-Based Geothermal Reservoirs Geothermal Lab Call Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Advancing Reactive Tracer Methods for Measuring Thermal Evolution in CO2- and Water-Based Geothermal Reservoirs Project Type / Topic 1 Laboratory Call for Submission of Applications for Research, Development and Analysis of Geothermal Technologies Project Type / Topic 2 Tracers and Tracer Interpretation Project Description The concepts and theory behind the use of heat-sensitive tracers to study the thermal evolution of geothermal reservoirs was developed in the late 1980's under the Hot Dry Rock Project. Those studies described-conceptually and mathematically-the application of reactive tracers to tracking thermal fronts and to reservoir sizing. Later mathematical treatments focused on application of a single reactive tracer test to recover the temperature profile of a single streamtube. Previous tracer work has mainly focused on identifying conservative tracers. In these studies, chemicals that degraded at reservoir temperatures were discarded. Benzoic acids and dicarboxylic acids, which were found by Adams to degrade, may be useful as reactive tracers. Organic esters and amide tracers that undergo hydrolysis have been investigated and their use as reactive tracers appears feasible over a temperature range of 100ºC to 275ºC. However their reaction rates are pH dependent and sorption reactions have not been evaluated. While reactive tracer parameters have been measured in the lab, reactive tracers have not been extensively tested in the field. Thus, while reactive tracers appear to be a promising means of monitoring the thermal evolution of a geothermal reservoir, the concept has yet to be tested at the scale necessary for successful implementation, and tools for analyzing results of such tracer tests under the non-ideal conditions of an actual geothermal system have yet to be developed.

277

DOE/EA-1310: Environmental Assessment for Decontamination and Dismantlement of the Advanced Reactivity Measurement Facility and Couples Fast Reactivity Measurements Facility at the Idaho National Engineering and Environmental Laboratory  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

0 0 March 2000 Environmental Assessment for Decontamination and Dismantlement of the Advanced Reactivity Measurement Facility and Coupled Fast Reactivity Measurements Facility at the Idaho National Engineering and Environmental Laboratory DOE/EA-1310 Environmental Assessment for Decontamination and Dismantlement of the Advanced Reactivity Measurement Facility and Coupled Fast Reactivity Measurements Facility at the Idaho National Engineering and Environmental Laboratory Published March 2000 Prepared for the U.S. Department of Energy Idaho Operations Office iii CONTENTS ACRONYMS ............................................................................................................................... v HELPFUL INFORMATION ........................................................................................................

278

Installation of reactive metals groundwater collection and treatment systems  

SciTech Connect

Three groundwater plumes contaminated with volatile organic compounds (VOCs) and radionuclides at the Rocky Flats Environmental Technology Site are scheduled for remediation by 1999 based on the Rocky Flats Cleanup Agreement (RFCA) (DOE, 1996). These three plumes are among the top 20 environmental cleanup sites at Rocky Flats. One of these plumes, the Mound Site Plume, is derived from a previous drum storage area, and daylights as seeps near the South Walnut Creek drainage. Final design for remediation of the Mound Site Plume has been completed based on use of reactive metals to treat the contaminated groundwater, and construction is scheduled for early 1998. The two other plumes, the 903 Pad/Ryan`s Pit and the East Trenches Plumes, are derived from VOCs either from drums that leaked or that were disposed of in trenches. These two plumes are undergoing characterization and conceptual design in 1998 and construction is scheduled in 1999. The contaminants of concern in these plumes are tetrachloroethene, trichloroethene, carbon tetrachloride and low levels of uranium and americium.

Hopkins, J.K.; Primrose, A.L. [Rocky Mountain Remediation Services, LLC, Golden, CO (United States). Rocky Flats Environmental Technology Site; Vogan, J. [EnviroMetal Technologies, Inc., Guelph, Ontario (Canada); Uhland, J. [Kaiser-Hill, LLC, Golden, CO (United States). Rocky Flats Environmental Technology Site

1998-07-01T23:59:59.000Z

279

Reactive gas atomization processing for Fe-based ODS alloys  

SciTech Connect

Gas atomization reaction synthesis was employed as a simplified method for processing oxide dispersion forming precursor Fe-based powders (e.g., Fe–Cr–Y–Hf). During this process a reactive atomization gas (i.e., Ar–O2) was used to oxidize the powder surfaces during primary break-up and rapid solidification of the molten alloy. This resulted in envelopment of the powders by an ultra-thin (t < 50 nm) metastable Cr-enriched oxide shell that was used as a vehicle to transport oxygen into the consolidated microstructure. Subsequent elevated temperature heat treatment promoted thermodynamically driven oxygen exchange reactions between trapped films of Cr-enriched oxide and internal (Y, Hf)-enriched intermetallic precipitates, resulting in highly stable nano-metric mixed oxide dispersoids (i.e., Y–Hf–O) that were identified with X-ray diffraction. Transmission electron microscopy and atom probe tomography results also revealed that the size and distribution of the dispersoids were found to depend strongly on the original rapidly solidified microstructure. To exploit this, several oxide dispersion strengthened microstructures were engineered from different powder particle size ranges, illustrating microstructural control as a function of particle solidification rate. Additionally, preliminary thermal–mechanical processing was used to develop a fine scale dislocation substructure for ultimate strengthening of the alloy.

Rieken, Joel R [Ames Laboratory; Anderson, Iver E [Ames Laboratory; Kramer, Matthew J [Ames Laboratory; Odette, G R [University of California; Stergar, E [University of California; Haney, E [University of California

2011-08-24T23:59:59.000Z

280

Modern integral equation techniques for quantum reactive scattering theory  

SciTech Connect

Rigorous calculations of cross sections and rate constants for elementary gas phase chemical reactions are performed for comparison with experiment, to ensure that our picture of the chemical reaction is complete. We focus on the H/D+H{sub 2} {yields} H{sub 2}/DH + H reaction, and use the time independent integral equation technique in quantum reactive scattering theory. We examine the sensitivity of H+H{sub 2} state resolved integral cross sections {sigma}{sub v{prime}j{prime},vj}(E) for the transitions (v = 0,j = 0) to (v{prime} = 1,j{prime} = 1,3), to the difference between the Liu-Siegbahn-Truhlar-Horowitz (LSTH) and double many body expansion (DMBE) ab initio potential energy surfaces (PES). This sensitivity analysis is performed to determine the origin of a large discrepancy between experimental cross sections with sharply peaked energy dependence and theoretical ones with smooth energy dependence. We find that the LSTH and DMBE PESs give virtually identical cross sections, which lends credence to the theoretical energy dependence.

Auerbach, S.M.

1993-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Three-dimensional visualization of reactive flows in complex geometries  

SciTech Connect

The visualization of fluid flows has become more challenging, as recent advancements in computational methods have increased the complexity and size of simulations. Our objective is to develop a flexible flow visualization tool for fluid simulations that include the full physics and geometrical complexities found in modeling practical combustion systems, such as internal combustion engines. The challenges to flow visualization come from: (1) the large simulation output, especially when using massively parallel computers; (2) the increasingly complex geometries that include moving surfaces such as pistons and valves; (3) the complex physical phenomena in realistic problems of fuel injection, combustion fronts, boundary flows, and large scale turbulence; and (4) the numerical complexity of indirect addressing of computational elements, variable mesh connectivity, distorted elements, and moving meshes. We have developed a visualization program that addresses these complexities. The program was developed as a post-processor to the KIVA family of codes for reactive flow simulations. Because of the complexity of the KIVA codes, the visualization program is very versatile and applicable to any code with meshes of arbitrary hexahedrons. No comparable commercial visualization package could be found. To visualize the fluid flow, we use mass-less tracer particles that follow the movement of the fluid as determined from output files from the simulation. The movement of the tracer particles is based on a second-order spatial and temporal interpolation of the fluid velocities from successive simulation output files. The visualization program runs on a Silicon Graphics IRIS GTX workstation.

Fairfield, M.S.

1995-02-01T23:59:59.000Z

282

Etching radical controlled gas chopped deep reactive ion etching  

DOE Patents (OSTI)

A method for silicon micromachining techniques based on high aspect ratio reactive ion etching with gas chopping has been developed capable of producing essentially scallop-free, smooth, sidewall surfaces. The method uses precisely controlled, alternated (or chopped) gas flow of the etching and deposition gas precursors to produce a controllable sidewall passivation capable of high anisotropy. The dynamic control of sidewall passivation is achieved by carefully controlling fluorine radical presence with moderator gasses, such as CH.sub.4 and controlling the passivation rate and stoichiometry using a CF.sub.2 source. In this manner, sidewall polymer deposition thicknesses are very well controlled, reducing sidewall ripples to very small levels. By combining inductively coupled plasmas with controlled fluorocarbon chemistry, good control of vertical structures with very low sidewall roughness may be produced. Results show silicon features with an aspect ratio of 20:1 for 10 nm features with applicability to nano-applications in the sub-50 nm regime. By comparison, previous traditional gas chopping techniques have produced rippled or scalloped sidewalls in a range of 50 to 100 nm roughness.

Olynick, Deidre; Rangelow, Ivo; Chao, Weilun

2013-10-01T23:59:59.000Z

283

Apparatus for continuously referenced analysis of reactive components in solution  

DOE Patents (OSTI)

A continuously referenced apparatus for measuring the concentration of a reactive chemical species in solution comprises in combination conduit means for introducing a sample solution, means for introducing one or more reactants into a sample solution, a reaction zone in fluid communication with said conduit means wherein a first chemical reaction occurs between said species and reactants, and a stream separator disposed within the conduit means for separating the sample solution into a sample stream and a reference stream. An enzymatic reactor is disposed in fluid communication with only the sample stream wherein a second reaction takes place between the said reactants, species, and reactor enzymes causing the consumption or production of an indicator species in just the sample stream. Measurement means such as a photometric system are disposed in communication with the sample and reference streams, and the outputs of the measurement means are compared to provide a blanked measurement of the concentration of indicator species. A peristaltic pump is provided to equalize flow through the apparatus by evacuation. The apparatus is particularly suitable for measurement of isoenzymes in body tissues or fluids.

Bostick, William D. (Oak Ridge, TN); Denton, Mark S. (Oak Ridge, TN); Dinsmore, Stanley R. (Norris, TN)

1981-01-01T23:59:59.000Z

284

Predictive modeling of reactive wetting and metal joining.  

SciTech Connect

The performance, reproducibility and reliability of metal joints are complex functions of the detailed history of physical processes involved in their creation. Prediction and control of these processes constitutes an intrinsically challenging multi-physics problem involving heating and melting a metal alloy and reactive wetting. Understanding this process requires coupling strong molecularscale chemistry at the interface with microscopic (diffusion) and macroscopic mass transport (flow) inside the liquid followed by subsequent cooling and solidification of the new metal mixture. The final joint displays compositional heterogeneity and its resulting microstructure largely determines the success or failure of the entire component. At present there exists no computational tool at Sandia that can predict the formation and success of a braze joint, as current capabilities lack the ability to capture surface/interface reactions and their effect on interface properties. This situation precludes us from implementing a proactive strategy to deal with joining problems. Here, we describe what is needed to arrive at a predictive modeling and simulation capability for multicomponent metals with complicated phase diagrams for melting and solidification, incorporating dissolutive and composition-dependent wetting.

van Swol, Frank B.

2013-09-01T23:59:59.000Z

285

Spectroscopy, Thermochemistry, and Reactivity of Lanthanide and Actinide Molecules  

SciTech Connect

The research undertaken under this grant is described in this document. The document describes progress in the construction of an instrument for recording photodissociation action spectra of mass-selected cryo-cooled cations. The instrument is not yet functional, but we anticipate trapping ions and conducting photodissociation experiments before the end of the year. It also describes resonant two-photon ionization spectra that have been recorded for uranium mononitride (UN) in the visible portion of the spectrum. These experiments are still underway at the present time. Although the spectra are a bit difficult to properly fit, due to upper state perturbations, it appears that the molecule has a ground state with {Omega} = 3.5 and a bond length of approximately 1.76 {angstrom}. Finally, results on the thermochemistry and reactivity of Th{sup +} are presented. In these studies the bond energies of the following bonds have been determined: D{sub 0}(Th{sup +}-2O) = 10.2 {+-} 0.2 eV; D0(Th{sup +}-N) = 6.69 {+-} 0.35 eV; D0(Th{sup +}-O) = 8.40 {+-} 0.28 eV; D{sub 0}(OTh{sup +}-O) = 1.8 {+-} 0.4 eV.

Morse, Michael D.; Armentrout, Peter B.

2012-08-16T23:59:59.000Z

286

Final Report- Rejuvenating Permeable Reactive Barriers by Chemical Flushing, U.S. Environmental Protection Agency Region 8 Support  

Energy.gov (U.S. Department of Energy (DOE))

Final Report - Rejuvenating Permeable Reactive Barriers by Chemical Flushing, U.S. Environmental Protection Agency Region 8 Support

287

TOUGHREACT Version 2.0: A simulator for subsurface reactive transport under non-isothermal multiphase flow conditions  

Science Conference Proceedings (OSTI)

TOUGHREACT is a numerical simulation program for chemically reactive non-isothermal flows of multiphase fluids in porous and fractured media, and was developed by introducing reactive chemistry into the multiphase fluid and heat flow simulator TOUGH2 ... Keywords: CO2 geological storage, Environmental remediation, Multi-phase flow, Nuclear waste geological disposal, Reactive transport, TOUGHREACT

Tianfu Xu; Nicolas Spycher; Eric Sonnenthal; Guoxiang Zhang; Liange Zheng; Karsten Pruess

2011-06-01T23:59:59.000Z

288

Demonstration of the reactivity constraint approach on SNL's annual core research reactor  

Science Conference Proceedings (OSTI)

This paper reports on the initial demonstration of the reactivity constraint approach and its implementing algorithm, the MIT-CSDL Non-Linear Digital Controller, on the annual core research reactor (ACCR) that is operated by the Sandia National Laboratories. This demonstration constituted the first use of reactivity constraints for the closed-loop, digital control of reactor power on a facility other than the Massachusetts Institute of Technology's (MIT's) research reactor (MITR-II). Also, because the ACRR and the MITR-II are of very different design, these trials established the generic nature of the reactivity constraint approach.

Bernard, J.A.; Kwok, K.S.; Wyant, F.J.; Thome, F.V.

1989-01-01T23:59:59.000Z

289

The Safe Storage Study for Autocatalytic Reactive Chemicals  

E-Print Network (OSTI)

In the U.S. Chemical Safety and Hazard Investigation Board (CSB) report, Improving Reactive Hazard Management, there are 37 out of 167 accidents, which occurred in a storage tank or a storage area. This fact demonstrates that thermal runaway problems in chemical storage processes have not been give enough attention. Hydroxylamine Nitrate (HAN) is an important member of the hydroxylamine compound family and its diluted aqueous solution is widely used in the nuclear industry for equipment decontamination. It is also used as a solid or aqueous propellant. Due to its instability and autocatalytic behavior, it has been involved in several incidents at the Hanford and Savannah River Sites (SRS). Much research has been conducted on HAN in different areas, such as combustion mechanism, decomposition mechanism, and runaway behavior. However, the autocatalytic behavior of HAN at runaway stage has not been fully addressed due to its highly exothermic and rapid decomposition behavior. This work focuses on extracting its autocatalytic kinetics mechanism and studying its critical behavior from adiabatic calorimetry measurements. The lumped autocatalytic kinetics model, the associated model parameters and HAN critical condition are determined for the first time. The contamination effect of iron ions and nitric acid on diluted hydroxylamine nitrate solution is also studied. This work also identified the safe storage conditions for a small quantity HAN diluted solution with thermal explosion theory. Computational Fluid Dynamics (CFD) was used to further study the influence of natural convection and system scale on the critical behavior for a large quantity of chemical and thus proposed the practical storage guidelines for industrial practice.

Liu, Lijun

2009-08-01T23:59:59.000Z

290

Impact of C-reactive protein (CRP) on surfactant function  

Science Conference Proceedings (OSTI)

Plasma levels of the acute-phase reactant, C-reactive protein (CRP), increase up to one thousand-fold as a result of trauma or inflammation. CRP binds to phosphorylcholine (PC) in a calcium-ion dependent manner. The structural homology between PC and the major phospholipid component of surfactant, dipalmitoyl phosphatidylcholine (DPPC), led to the present study in which we examined if CRP levels might be increased in patients with adult respiratory distress syndrome (ARDS), and subsequently interfere with surfactant function. Our results showed that CRP levels in the bronchoalveolar fluid (BALF) was increased in patients with ARDS (97.8 +/- 84.2 micrograms/mg total protein vs. 4.04 +/- 2.2 micrograms/mg total protein in normals). Our results show that CRP binds to liposomes containing DPPC and phosphatidylglycerol (PG). As a result of this interaction, CRP inhibits the surface activity of a PG-DPPC mixture when tested with a Wilhelmy surfactometer or with the Enhorning pulsating bubble apparatus. Furthermore, the surface activity of a clinically used surfactant replacement, Surfactant TA (2 mg/ml), was also severely impaired by CRP in a dose-dependent manner (doses used ranging from 24.5 to 1,175 micrograms/ml). In contrast, human serum albumin (HSA) at 500 and 900 micrograms/ml had no inhibitory effect on Surfactant TA surface activity. These results suggest that CRP, although not an initiating insult in ARDS, may contribute to the subsequent abnormalities of surfactant function and thus the pathogenesis of the pulmonary dysfunction seen in ARDS.

Li, J.J.; Sanders, R.L.; McAdam, K.P.; Hales, C.A.; Thompson, B.T.; Gelfand, J.A.; Burke, J.F. (Shriners Burns Institute, Boston, MA (USA))

1989-12-01T23:59:59.000Z

291

Coupled modeling of non-isothermal multiphase flow, solute transport and reactive chemistry in porous and fractured media: 1. Model Development and Validation  

E-Print Network (OSTI)

multiphase reactive transport, in Reactive transport in porousporous and fractured media under non-isothermal multiphaseporous and fractured media under non-isothermal multiphase

Xu, Tianfu; Pruess, Karsten

1998-01-01T23:59:59.000Z

292

Argonne TTRDC - D3 (Downloadable Dynamometer Database) - 2012...  

NLE Websites -- All DOE Office Websites (Extended Search)

Chevrolet VOLT chevy volt front chevy volt rear 2012 Chevy Volt- front 2012 Chevy Volt- rear The Chevrolet Volt is the first production extended range electric vehicle (EREV)...

293

Combining thorium with burnable poison for reactivity control of a very long cycle BWR  

E-Print Network (OSTI)

The effect of utilizing thorium together with gadolinium, erbium, or boron burnable absorber in BWR fuel assemblies for very long cycle is investigated. Nuclear characteristics such as reactivity and power distributions ...

Inoue, Yuichiro, 1969-

2004-01-01T23:59:59.000Z

294

Distributed control of reactive power flow in a radial distribution circuit with high photovoltaic penetration  

E-Print Network (OSTI)

We show how distributed control of reactive power can serve to regulate voltage and minimize resistive losses in a distribution circuit that includes a significant level of photovoltaic (PV) generation. To demonstrate the technique, we consider a radial distribution circuit with a single branch consisting of sequentially-arranged residential-scale loads that consume both real and reactive power. In parallel, some loads also have PV generation capability. We postulate that the inverters associated with each PV system are also capable of limited reactive power generation or consumption, and we seek to find the optimal dispatch of each inverter's reactive power to both maintain the voltage within an acceptable range and minimize the resistive losses over the entire circuit. We assume the complex impedance of the distribution circuit links and the instantaneous load and PV generation at each load are known. We compare the results of the optimal dispatch with a suboptimal local scheme that does not require any com...

Turitsyn, Konstantin; Backhaus, Scott; Chertkov, Michael

2009-01-01T23:59:59.000Z

295

Investigation on Durability and Reactivity of Promising Metal Oxide Sorbents During Sulfidation and Regeneration  

SciTech Connect

Research activities and efforts of this research project were concentrated on formulating various metal oxide sorbents with various additives under various formulation conditions, conducting experiments on initial reactivity of formulated sorbents with hydrogen sulfide, and testing hardness of formulated sorbents. Experiments on reactivity of formulated metal oxide sorbents with wet hydrogen sulfide contained in a simulated coal gas mixture were carried out for 120 seconds at 550 o C (see Table 1) to evaluate reactivity of formulated sorbents with hydrogen sulfide. Hardness of formulated sorbents was evaluated in addition to testing their reactivity with hydrogen sulfide. A typical simulated coal gas mixture consists of 9107-ppm hydrogen sulfide (0.005 g; 1 wt %), 0.085-g water (15.84 wt %), 0.0029-g hydrogen (0.58 wt %), and 0.4046-g nitrogen (81.34 wt%).

K. C. Kwon

1997-05-01T23:59:59.000Z

296

Phototriggered production of reactive oxygen species by TIO2 nanospheres and rods  

Science Conference Proceedings (OSTI)

We present the study of reactive oxygen species production under the light irradiation of two different types of TiO2 nanocrystals. Both TiO2 spheric NPs and anisotropic nanorods were investigated using activation of the horseradish ...

Bianca Geiseler, Marko Miljevic, Philipp Müller, Ljiljana Fruk

2012-01-01T23:59:59.000Z

297

Reactivity of Ti2AlC with SiC Fibers and Powders up to ...  

Science Conference Proceedings (OSTI)

Herein we investigated the reactivity of Ti2AlC [3ONE2] with SiC fibers [Avco Specialty Materials and Nippon Carbon Co.] and fine SiC powders [Superior ...

298

Mild coal pretreatment to improve liquefaction reactivity. Quarterly technical progress report, June--August 1991  

SciTech Connect

This report describes work completed during the fourth quarter of a three year project to study the effects of mild chemical pretreatment on coal dissolution reactivity during low severity liquefaction or coal/oil coprocessing. The overall objective of this research is to elucidate changes in the chemical and physical structure of coal by pretreating with methanol or other simple organic solvent and a trace amount of hydrochloric acid and measure the influence of these changes on coal dissolution reactivity. This work is part of a larger effort to develop a new coal liquefaction or coal/oil coprocessing scheme consisting of three main process steps: (1) mile pretreatment of the feed coal to enhance dissolution reactivity and dry the coal, (2) low severity thermal dissolution of the pretreated coal to obtain a very reactive coal-derived residual material amenable to upgrading, and (3) catalytic upgrading of the residual products to distillate liquids.

Miller, R.L.

1991-12-31T23:59:59.000Z

299

Integration of reactive polymeric nanofilms into a low-power electromechanical switch for selective chemical sensing  

E-Print Network (OSTI)

This paper presents the fabrication and demonstration of an ultrathin microelectromechanical chemical sensing device. Microcantilevers are etched from 100-nm-thick silicon nitride, and a 75-nm-thick reactive copolymer film ...

Arora, William J.

300

Numerical Modeling of the Turbulent Fluxes of Chemically Reactive Trace Gases in the Atmospheric Boundary Layer  

Science Conference Proceedings (OSTI)

Turbulent fluxes of chemically reactive trace gases in the neutral atmospheric boundary layer (ABL) were simulated with a one-dimensional, coupled diffusion-chemistry model. The effects of rapid chemical reactions were included with a suite of ...

W. Gao; M. L. Wesely

1994-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
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We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Analysis of Reactivity Induced Accident for Control Rods Ejection with Loss of Cooling  

E-Print Network (OSTI)

Understanding of the time-dependent behavior of the neutron population in nuclear reactor in response to either a planned or unplanned change in the reactor conditions, is a great importance to the safe and reliable operation of the reactor. In the present work, the point kinetics equations are solved numerically using stiffness confinement method (SCM). The solution is applied to the kinetics equations in the presence of different types of reactivities and is compared with different analytical solutions. This method is also used to analyze reactivity induced accidents in two reactors. The first reactor is fueled by uranium and the second is fueled by plutonium. This analysis presents the effect of negative temperature feedback with the addition positive reactivity of control rods to overcome the occurrence of control rod ejection accident and damaging of the reactor. Both power and temperature pulse following the reactivity- initiated accidents are calculated. The results are compared with previous works and...

Saad, Hend Mohammed El Sayed; Wahab, Moustafa Aziz Abd El

2013-01-01T23:59:59.000Z

302

Molten Salt Multi-anode Reactive Alloy Coating(MARC) of Ta-W ...  

Science Conference Proceedings (OSTI)

In this study, Ta-W coated samples (Ta-7.31W, Ta-4.12W and Ta-1.92W) were prepared by multi-anode reactive alloy coating (MARC) process in molten salt ...

303

Assessment of the Economic Potential of Microgrids for Reactive Power Supply  

DOE Green Energy (OSTI)

As power generation from variable distributed energy resources (DER) grows, energy flows in the network are changing, increasing the requirements for ancillary services, including voltage support. With the appropriate power converter, DER can provide ancillary services such as frequency control and voltage support. This paper outlines the economic potential of DERs coordinated in a microgrid to provide reactive power and voltage support at its point of common coupling. The DER Customer Adoption Model assesses the costs of providing reactive power, given local utility rules. Depending on the installed DER, the cost minimizing solution for supplying reactive power locally is chosen. Costs include the variable cost of the additional losses and the investment cost of appropriately over-sizing converters or purchasing capacitors. A case study of a large health care building in San Francisco is used to evaluate different revenue possibilities of creating an incentive for microgrids to provide reactive power.

Appen, Jan von; Marnay, Chris; Stadler, Michael; Momber, Ilan; Klapp, David; Scheven, Alexander von

2011-05-01T23:59:59.000Z

304

Numerical Simulation of the Transport of Chemically Reactive Species under Land- and Sea-Breeze Circulations  

Science Conference Proceedings (OSTI)

The characteristics of the transport of chemically reactive species under land- and sea-breeze (LSB) circulations are investigated using a detailed transport/chemistry model, which includes 84 gas-phase and 10 heterogeneous chemical reactions. ...

Toshihiro Kitada; Gregory R. Carmichael; Leonard K. Peters

1984-08-01T23:59:59.000Z

305

Analysis of Reactivity Induced Accident for Control Rods Ejection with Loss of Cooling  

E-Print Network (OSTI)

Understanding of the time-dependent behavior of the neutron population in nuclear reactor in response to either a planned or unplanned change in the reactor conditions, is a great importance to the safe and reliable operation of the reactor. In the present work, the point kinetics equations are solved numerically using stiffness confinement method (SCM). The solution is applied to the kinetics equations in the presence of different types of reactivities and is compared with different analytical solutions. This method is also used to analyze reactivity induced accidents in two reactors. The first reactor is fueled by uranium and the second is fueled by plutonium. This analysis presents the effect of negative temperature feedback with the addition positive reactivity of control rods to overcome the occurrence of control rod ejection accident and damaging of the reactor. Both power and temperature pulse following the reactivity- initiated accidents are calculated. The results are compared with previous works and satisfactory agreement is found.

Hend Mohammed El Sayed Saad; Hesham Mohammed Mohammed Mansour; Moustafa Aziz Abd El Wahab

2013-06-05T23:59:59.000Z

306

Identification of Critical Voltage Control Areas and Determination of Required Reactive Power Reserves  

Science Conference Proceedings (OSTI)

The objective of this research project is to investigate and devise a methodology for identifying areas in power systems that are prone to voltage instability under particular operating conditions and contingencies. These areas, which are prone to instability due to their lack of reactive power reserves, are referred to as critical voltage control areas (VCAs). Once VCAs are identified, methods of determining their adequate reactive power reserve requirements to ensure secure system operation under all c...

2008-12-09T23:59:59.000Z

307

Study on Reactive Power and Voltage Control of Power Grid with Small Hydropower  

Science Conference Proceedings (OSTI)

When it is in the wet season and the load is low, reactive power surplus and voltage rise are caused by high-efficiency power generation of small hydropower and load reduction in Linjiang region, Baishan city, JiLin province. These problems, which exist ... Keywords: small hydro power, vally load, reactive power balance, the rise in voltage, generator in leading power factor on operation

Yaopeng Bai; Lijie Xu; Wei Wang

2010-06-01T23:59:59.000Z

308

ELECTROSTATIC PROBE DIAGNOSTICS ON THE LBL 10 AMPERE NEUTRAL BEAM ION SOURCE  

E-Print Network (OSTI)

speeds of .1 v/psec to 1 v/usec over a total range of 100sweep speed of .1 V/usec. A direct connection between time

Schoenberg, Kurt F.

2011-01-01T23:59:59.000Z

309

Application of Newton's optimal power flow in voltage/reactive power control  

Science Conference Proceedings (OSTI)

This paper considers an application of Newton's optimal power flow to the solution of the secondary voltage/reactive power control in transmission networks. An efficient computer program based on the latest achievements in the sparse matrix/vector techniques has been developed for this purpose. It is characterized by good robustness, accuracy and speed. A combined objective function appropriate for various system load levels with suitable constraints, for treatment of the power system security and economy is also proposed. For the real-time voltage/reactive power control, a suboptimal power flow procedure has been derived by using the reduced set of control variables. This procedure is based on the sensitivity theory applied to the determination of zones for the secondary voltage/reactive power control and corresponding reduced set of regulating sources, whose reactive outputs represent control variables in the optimal power flow program. As a result, the optimal power flow program output becomes a schedule to be used by operators in the process of the real-time voltage/reactive power control in both normal and emergency operating states.

Bjelogrlic, M.; Babic, B.S. (Electric Power Board of Serbia, Belgrade (YU)); Calovic, M.S. (Dept. of Electrical Engineering, University of Belgrade, Belgrade (YU)); Ristanovic, P. (Institute Nikola Tesla, Belgrade (YU))

1990-11-01T23:59:59.000Z

310

Reactive power interconnection requirements for PV and wind plants : recommendations to NERC.  

DOE Green Energy (OSTI)

Voltage on the North American bulk system is normally regulated by synchronous generators, which typically are provided with voltage schedules by transmission system operators. In the past, variable generation plants were considered very small relative to conventional generating units, and were characteristically either induction generator (wind) or line-commutated inverters (photovoltaic) that have no inherent voltage regulation capability. However, the growing level of penetration of non-traditional renewable generation - especially wind and solar - has led to the need for renewable generation to contribute more significantly to power system voltage control and reactive power capacity. Modern wind-turbine generators, and increasingly PV inverters as well, have considerable dynamic reactive power capability, which can be further enhanced with other reactive support equipment at the plant level to meet interconnection requirements. This report contains a set of recommendations to the North-America Electricity Reliability Corporation (NERC) as part of Task 1-3 (interconnection requirements) of the Integration of Variable Generation Task Force (IVGTF) work plan. The report discusses reactive capability of different generator technologies, reviews existing reactive power standards, and provides specific recommendations to improve existing interconnection standards.

McDowell, Jason (General Electric, Schenectady, NY); Walling, Reigh (General Electric, Schenectady, NY); Peter, William (SunPower, Richmond, CA); Von Engeln, Edi (NV Energy, Reno, NV); Seymour, Eric (AEI, Fort Collins, CO); Nelson, Robert (Siemens Wind Turbines, Orlando, FL); Casey, Leo (Satcon, Boston, MA); Ellis, Abraham; Barker, Chris. (SunPower, Richmond, CA)

2012-02-01T23:59:59.000Z

311

Energy Storage and Reactive Power Compensator in a Large Wind Farm: Preprint  

Science Conference Proceedings (OSTI)

The size of wind farm power systems is increasing, and so is the number of wind farms contributing to the power systems network. The size of wind turbines is also increasing--from less than 1 MW a few years ago to the 2- to 3-MW machines being installed today and the 5-MW machines under development. The interaction of the wind farm, energy storage, reactive power compensation, and the power system network is being investigated. Because the loads and the wind farms' output fluctuate during the day, the use of energy storage and reactive power compensation is ideal for the power system network. Energy storage and reactive power compensation can minimize real/reactive power imbalances that can affect the surrounding power system. In this paper, we will show how the contribution of wind farms affects the power distribution network and how the power distribution network, energy storage, and reactive power compensation interact when the wind changes. We will also investigate the size of the components in relation to each other and to the power system.

Muljadi, E.; Butterfield, C. P.; Yinger, R.; Romanowitz, H.

2003-10-01T23:59:59.000Z

312

Zero Valent Iron: Impact of Anions Present during Synthesis on Subsequent Nanoparticle Reactivity  

SciTech Connect

Zero-valent iron particles are an effective remediation technology for groundwater contaminated with halogenated organic compounds. In particular, nano-scale zero-valent iron is a promising material for remediation due to its high specific surface area, which results in faster rate constants and more effective use of the iron. An aspect of iron nanoparticle reactivity that has not been explored is the impact of anions present during iron metal nanoparticle synthesis. Solutions containing chloride, phosphate, sulfate, and nitrate anions and ferric ions were used to generate iron oxide nanoparticles. The resulting materials were dialyzed to remove dissolved byproducts and then dried and reduced by hydrogen gas at high temperature. The reactivity of the resulting zero valent iron nanoparticles was quantified by monitoring the kinetics as well as products of carbon tetrachloride reduction, and significant differences in reactivity and chloroform yield were observed. The reactivity of nanoparticles prepared in the presence of sulfate and phosphate demonstrated the highest reactivity and chloroform yield. Furthermore, substantial variations in the solid-state products of oxidation (magnetite, iron sulfide, and goethite, among others) were also observed.

Moore, Kirsten; Forsberg, Brady; Baer, Donald R.; Arnold, William A.; Penn, R. Lee

2011-10-01T23:59:59.000Z

313

A Preliminary Analysis of the Economics of Using Distributed Energy as a Source of Reactive Power Supply  

DOE Green Energy (OSTI)

A major blackout affecting 50 million people in the Northeast United States, where insufficient reactive power supply was an issue, and an increased number of filings made to the Federal Energy Regulatory Commission by generators for reactive power has led to a closer look at reactive power supply and compensation. The Northeastern Massachusetts region is one such area where there is an insufficiency in reactive power compensation. Distributed energy due to its close proximity to loads seems to be a viable option for solving any present or future reactive power shortage problems. Industry experts believe that supplying reactive power from synchronized distributed energy sources can be 2 to 3 times more effective than providing reactive support in bulk from longer distances at the transmission or generation level. Several technology options are available to supply reactive power from distributed energy sources such as small generators, synchronous condensers, fuel cells or microturbines. In addition, simple payback analysis indicates that investments in DG to provide reactive power can be recouped in less than 5 years when capacity payments for providing reactive power are larger than $5,000/kVAR and the DG capital and installation costs are lower than $30/kVAR. However, the current institutional arrangements for reactive power compensation present a significant barrier to wider adoption of distributed energy as a source of reactive power. Furthermore, there is a significant difference between how generators and transmission owners/providers are compensated for reactive power supplied. The situation for distributed energy sources is even more difficult, as there are no arrangements to compensate independent DE owners interested in supplying reactive power to the grid other than those for very large IPPs. There are comparable functionality barriers as well, as these smaller devices do not have the control and communications requirements necessary for automatic operation in response to local or system operators. There are no known distributed energy asset owners currently receiving compensation for reactive power supply or capability. However, there are some cases where small generators on the generation and transmission side of electricity supply have been tested and have installed the capability to be dispatched for reactive power support. Several concerns need to be met for distributed energy to become widely integrated as a reactive power resource. The overall costs of retrofitting distributed energy devices to absorb or produce reactive power need to be reduced. There needs to be a mechanism in place for ISOs/RTOs to procure reactive power from the customer side of the meter where distributed energy resides. Novel compensation methods should be introduced to encourage the dispatch of dynamic resources close to areas with critical voltage issues. The next phase of this research will investigate in detail how different options of reactive power producing DE can compare both economically and functionally with shunt capacitor banks. Shunt capacitor banks, which are typically used for compensating reactive power consumption of loads on distribution systems, are very commonly used because they are very cost effective in terms of capital costs. However, capacitor banks can require extensive maintenance especially due to their exposure to lightning at the top of utility poles. Also, it can be problematic to find failed capacitor banks and their maintenance can be expensive, requiring crews and bucket trucks which often requires total replacement. Another shortcoming of capacitor banks is the fact that they usually have one size at a location (typically sized as 300, 600, 900 or 1200kVAr) and thus don't have variable range as do reactive power producing DE, and cannot respond to dynamic reactive power needs. Additional future work is to find a detailed methodology to identify the hidden benefit of DE for providing reactive power and the best way to allocate the benefit among customers, utilities, transmission companies or RTOs.

Li, Fangxing [ORNL; Kueck, John D [ORNL; Rizy, D Tom [ORNL; King, Thomas F [ORNL

2006-04-01T23:59:59.000Z

314

ORNL/CP-97155 Instantaneous Reactive Power and Power Factor of  

Office of Scientific and Technical Information (OSTI)

ORNL/CP-97155 ORNL/CP-97155 Instantaneous Reactive Power and Power Factor of Instantaneous Phasor s ' 4 . L;/, Oak Ridge National Laboratory* P f Senior Member &Eb "'ii Lf/ .. John S. Hsu 4- p d Post Office Box 2009, MS 8038 Oak Ridge, Tennessee 3783 1-8038 Key wordr: Instantaneous reactive power, Symmetrical property, Instantaiteous phasors, Phasors of one phase, n r e e phases. Abstract The unique property of instantaneous phasors is that at any instant the instantaneous three-phase currents and voltages can be represented by a set of balanced phasors. The instantaneous reactive power and the concept of instantaneous power factor can be clearly understood from the instantaneous phasors. This provides a theoretical foundation for power quality monitoring, diagnostics,

315

Porous desulfurization sorbent pellets containing a reactive metal oxide and an inert zirconium compound  

DOE Patents (OSTI)

Sorbent pellets for removing hydrogen sulfide from coal gas are prepared by combining a reactive oxide, in particular zinc oxide, with a zirconium compound such as an oxide, silicate, or aluminate of zirconium, and an inorganic binder and pelletizing and calcining the mixture. Alternately, the zinc oxide may be replaced by copper oxide or a combination of copper, molybdenum, and manganese oxides. The pellet components may be mixed in dry form, moistened to produce a paste, and converted to pellets by forming an aqueous slurry of the components and spray drying the slurry, or the reactive oxide may be formed on existing zirconium-containing catalyst-carrier pellets by infusing a solution of a salt of the active metal onto the existing pellets and firing at a high temperature to produce the oxide. Pellets made according to this invention show a high reactivity with hydrogen sulfide and durability such as to be useful over repeated cycles of sorption and regeneration.

Gardner, Todd H.; Gasper-Galvin, Lee D.

1996-12-01T23:59:59.000Z

316

Reactivity worth measurements at the IPEN/MB-01 nuclear reactor  

Science Conference Proceedings (OSTI)

Researches that aim to improve the performance of neutron transport codes and quality of nuclear cross section databases are very important to increase the accuracy of simulations and the quality of the analysis and prediction of phenomena in the nuclear field. In this context, relevant experimental data such as reactivity worth measurements are needed. The objective of this work was to perform a series of experiments of reactivity worth measurements, using a digital reactivity meter developed at IPEN. The experiments employed small metallic and ceramic samples inserted in the central region of the core of the experimental IPEN/MB-01 reactor. The theoretical analysis was performed by the MCNP-5 reactor physics code, developed and maintained by Los Alamos National Laboratory, and the ENDF/B-VII.0 nuclear data library.

Pinto, Leticia Negrao; Santos, Adimir dos [Nuclear Engineering Center, Nuclear and Energy Research Institute- IPEN/CNEN-SP (Brazil)

2013-05-06T23:59:59.000Z

317

Impact of exhaust gas recirculation (EGR) on the oxidative reactivity of diesel engine soot  

SciTech Connect

This paper expands the consideration of the factors affecting the nanostructure and oxidative reactivity of diesel soot to include the impact of exhaust gas recirculation (EGR). Past work showed that soot derived from oxygenated fuels such as biodiesel carries some surface oxygen functionality and thereby possesses higher reactivity than soot from conventional diesel fuel. In this work, results show that EGR exerts a strong influence on the physical properties of the soot which leads to enhanced oxidation rate. HRTEM images showed a dramatic difference between the burning modes of the soot generated under 0 and 20% EGR. The soot produced under 0% EGR strictly followed an external burning mode with no evidence of internal burning. In contrast, soot generated under 20% EGR exhibited dual burning modes: slow external burning and rapid internal burning. The results demonstrate clearly that highly reactive soot can be achieved by manipulating the physical properties of the soot via EGR. (author)

Al-Qurashi, Khalid; Boehman, Andre L. [The EMS Energy Institute, The Pennsylvania State University, 405 Academic Activities Bldg., University Park, PA 16802 (United States)

2008-12-15T23:59:59.000Z

318

A simple model for radial expansion reactivity in LMRs (liquid metal reactors)  

Science Conference Proceedings (OSTI)

Presented in this report is a simple analytical model developed for evaluating the radial expansion reactivity in small modular liquid metal reactors (LMRs). The present model is based on a non-leakage representation of the effective neutron multiplication factor. The resultant analytical expression for the radial expansion reactivity is simple and can be used directly in a system code for safety analyses. Applications of the present model to PRISM and SAFR resulted in a good agreement with the values reported by vendors. This agreement establishes that the large negative reactivity insertion resulting from LMR core radial expansion can be confirmed using a simple analytical approach, and thus is important in the current effort to evaluate the reactor inherent feedbacks for the PRISM and SAFR designs.

Cheng, H.S.; Van Tuyle, G.J.

1988-01-01T23:59:59.000Z

319

Reactive instabilities of lower hybrid-like waves in regions with parallel currents  

Science Conference Proceedings (OSTI)

The dispersion and reactive instabilities of obliquely propagating waves near the lower hybrid (LH) frequency are studied in plasma carrying a current parallel to the magnetic field. Possible applications of these instabilities include magnetic reconnection regions, where LH-like waves may accelerate and heat both ions and electrons. In plasmas with a bulk drift of electrons relative to the ions at speed v{sub d} along the magnetic field, the forward and backward propagating LH modes are shown to be replaced by four LH-like modes. Reactive instabilities are discovered here for a forward propagating mode with Re({omega}){approx_equal}k{sub ||}v{sub d}/2 and a backward propagating mode with Re({omega})cold plasma calculations and agree well, confirming that the discovered instabilities are reactive. In the cold plasma limit, the forward and backward propagating instabilities occur for v{sub d} below and above some thresholds, respectively.

Verdon, A. L.; Cairns, Iver H.; Melrose, D. B.; Robinson, P. A. [School of Physics, University of Sydney, Sydney, New South Wales 2006 (Australia)

2011-05-15T23:59:59.000Z

320

Efficient DC-DC switch regulator : applied iterative learning and anti-windup control  

E-Print Network (OSTI)

Response with 5 Volt Reference Signal . . . . . . . Responsez) K I (z) K D (z) F (z) S(z) L Q q P V R Units (SI) voltsvolts volts volts volts amps amps volts volts volts volts

Raley, Jack

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Performance Assessment and Recommendations for Rejuvenation of a Permeable Reactive Barrier: Cotter Corporation’s Cañon City, Colorado, Uranium Mill  

Energy.gov (U.S. Department of Energy (DOE))

Performance Assessment and Recommendations for Rejuvenation of a Permeable Reactive Barrier: Cotter Corporation’s Canon City, Colorado, Uranium Mill (April 2005)

322

Cold Reactive Collisions between Laser-Cooled Ions and Velocity-Selected Neutral Molecules  

Science Conference Proceedings (OSTI)

We report a new experimental method to study reactive ion-molecule collisions at very low temperatures. A source of laser-cooled ions in a linear Paul trap has been combined with a quadrupole-guide velocity selector to investigate the reaction of Ca{sup +} with CH{sub 3}F at collision energies E{sub coll}/k{sub B}{>=}1 K with single-particle sensitivity. The technique represents a general approach to study reactive collisions between ions and polar molecules over a wide temperature range down to the cold regime.

Willitsch, Stefan; Bell, Martin T.; Gingell, Alexander D.; Procter, Simon R.; Softley, Timothy P. [Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Oxford OX1 3TA (United Kingdom)

2008-02-01T23:59:59.000Z

323

CASMO5/TSUNAMI-3D spent nuclear fuel reactivity uncertainty analysis  

Science Conference Proceedings (OSTI)

The CASMO5 lattice physics code is used in conjunction with the TSUNAMI-3D sequence in ORNL's SCALE 6 code system to estimate the uncertainties in hot-to-cold reactivity changes due to cross-section uncertainty for PWR assemblies at various burnup points. The goal of the analysis is to establish the multiplication factor uncertainty similarity between various fuel assemblies at different conditions in a quantifiable manner and to obtain a bound on the hot-to-cold reactivity uncertainty over the various assembly types and burnup attributed to fundamental cross-section data uncertainty. (authors)

Ferrer, R.; Rhodes, J. [Studsvik Scandpower, Inc., 504 Shoup Ave., Idaho Falls, ID 83402 (United States); Smith, K. [Dept. of Nuclear Science and Engineering, Massachusetts Inst. of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States)

2012-07-01T23:59:59.000Z

324

Reactivation or expansion of Hotel Baker Hydro plant. Feasibility assessment report  

SciTech Connect

The Hotel Baker Hydroelectric Power plant, built in 1928 at St. Charles, IL., has two generating units which until 1970 supplied the hotel with 100 kW output at 6 ft. head. The feasibility of reactivating, upgrading, or replacing these units to again supply power for the hotel was evaluated considering installation and operating costs, financing requirements, environmental impacts, and regulatory requirements. It was concluded that the reactivation project is marginally attractive only with full use of the power output by an expanded hotel and if electric utility rates increase at 8% per year. (LCL)

1979-03-01T23:59:59.000Z

325

Scalable Distributed Automation System: Scalable Real-time Decentralized Volt/VAR Control  

SciTech Connect

GENI Project: Caltech is developing a distributed automation system that allows distributed generators—solar panels, wind farms, thermal co-generation systems—to effectively manage their own power. To date, the main stumbling block for distributed automation systems has been the inability to develop software that can handle more than 100,000 distributed generators and be implemented in real time. Caltech’s software could allow millions of generators to self-manage through local sensing, computation, and communication. Taken together, localized algorithms can support certain global objectives, such as maintaining the balance of energy supply and demand, regulating voltage and frequency, and minimizing cost. An automated, grid-wide power control system would ease the integration of renewable energy sources like solar power into the grid by quickly transmitting power when it is created, eliminating the energy loss associated with the lack of renewable energy storage capacity of the grid.

None

2012-03-01T23:59:59.000Z

326

Effect of gigaelectron volt Au-ion irradiation on the characteristics of ultrananocrystalline diamond films  

SciTech Connect

The effect of 2.245 GeV Au-ion irradiation/postannealing processes on the electron field emission (EFE) properties of ultrananocrystalline diamond (UNCD) films was investigated. Au-ion irradiation with a fluence of around 8.4x10{sup 13} ions/cm{sup 2} is required to induce a large improvement in the EFE properties of the UNCD films. Postannealing the Au-ion irradiated films at 1000 deg. C for 1 h slightly degraded the EFE properties of the films but the resulting EFE behavior was still markedly superior to that of pristine UNCD films. Transmission electron microscopy examinations revealed that the EFE properties of the UNCD films are primarily improved by Au-ion irradiation/postannealing processes because of the formation of nanographites along the trajectory of the irradiating ions, which results in an interconnected path for electron transport. In contrast, the induction of grain growth process due to Au-ion irradiation in UNCD films is presumed to insignificantly degrade the EFE properties for the films as the aggregates are scarcely distributed and do not block the electron conducting path.

Chen, Huang-Chin; Teng, Kuang-Yau; Tang, Chen-Yau; Lin, I-Nan [Department of Physics, Tamkang University, Tamsui, Taiwan 251 (China); Sundaravel, Balakrishnan [Materials Science Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India); Amirthapandian, Sankarakumar [Materials Science Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India); Institut fuer Halbleiteroptik und Funktionelle Grenzflaechen, Universitaet Stuttgart, Allmandring 3, 70569 Stuttgart (Germany)

2010-12-15T23:59:59.000Z

327

Grid Strategy 2011: Conservation Voltage Reduction and Volt VAR Optimization in the Smart Grid  

Science Conference Proceedings (OSTI)

Beginning in the 1970s with the oil embargo, utilities began looking for ways to increase the efficiency of the power distribution system, to reduce peak demand, and to conserve energy. During this period, several utilities began to test the concept of lowering the voltage to lower the demand and energy consumption on the power delivery system. As climate change and global warming became serious issues in the early 2000s, utilities began looking at Conservation Voltage Reduction (CVR) programs once again...

2011-11-11T23:59:59.000Z

328

Pages that link to "CyVolt Energy Systems" | Open Energy Information  

Open Energy Info (EERE)

(20 | 50 | 100 | 250 | 500) Washington's 7th congressional district ( links) Seattle, Washington ( links) King County, Washington ( links) View (previous 50...

329

Behavioral design to model a reactive decision of an expert in geothermal wells  

Science Conference Proceedings (OSTI)

Software design based on agents represents a new perspective for computer science and more specifically, for Artificial Intelligence. It is a new theory that has innovated the analysis, design and implementation of system software. The design of agents ... Keywords: Artificial Intelligence, Autonomous action, Behavioral analysis, Cognitive models, Geothermal wells, Inverse problem, Multi-agent architecture, Reactive agents, Subjective domain, Temperature formation

Ana Lilia Laureano-Cruces; Gilberto Espinosa-Paredes

2005-04-01T23:59:59.000Z

330

doi:10.1155/2011/839682 Review Article Haptenation: Chemical Reactivity and Protein Binding  

E-Print Network (OSTI)

Copyright © 2011 Itai Chipinda et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Low molecular weight chemical (LMW) allergens are commonly referred to as haptens. Haptens must complex with proteins to be recognized by the immune system. The majority of occupationally related haptens are reactive, electrophilic chemicals, or are metabolized to reactive metabolites that form covalent bonds with nucleophilic centers on proteins. Nonelectrophilic protein binding may occur through disulfide exchange, coordinate covalent binding onto metal ions on metalloproteins or of metal allergens, themselves, to the major histocompatibility complex. Recent chemical reactivity kinetic studies suggest that the rate of protein binding is a major determinant of allergenic potency; however, electrophilic strength does not seem to predict the ability of a hapten to skew the response between Th1 and Th2. Modern proteomic mass spectrometry methods that allow detailed delineation of potential differences in protein binding sites may be valuable in predicting if a chemical will stimulate an immediate or delayed hypersensitivity. Chemical aspects related to both reactivity and protein-specific binding are discussed. 1.

Itai Chipinda; Justin M. Hettick; Paul D. Siegel

2011-01-01T23:59:59.000Z

331

Reactivity Controlled Compression Ignition (RCCI) Combustion on a Multi-Cylinder Light-Duty Diesel Engine  

Science Conference Proceedings (OSTI)

Reactivity controlled compression ignition is a low-temperature combustion technique that has been shown, both in computational fluid dynamics modeling and single-cylinder experiments, to obtain diesel-like efficiency or better with ultra-low nitrogen oxide and soot emissions, while operating primarily on gasoline-like fuels. This paper investigates reactivity controlled compression ignition operation on a four-cylinder light-duty diesel engine with production-viable hardware using conventional gasoline and diesel fuel. Experimental results are presented over a wide speed and load range using a systematic approach for achieving successful steady-state reactivity controlled compression ignition combustion. The results demonstrated diesel-like efficiency or better over the operating range explored with low engine-out nitrogen oxide and soot emissions. A peak brake thermal efficiency of 39.0% was demonstrated for 2600 r/min and 6.9 bar brake mean effective pressure with nitrogen oxide emissions reduced by an order of magnitude compared to conventional diesel combustion operation. Reactivity controlled compression ignition emissions and efficiency results are compared to conventional diesel combustion operation on the same engine.

Curran, Scott [ORNL; Hanson, Reed M [ORNL; Wagner, Robert M [ORNL

2012-01-01T23:59:59.000Z

332

Second-order splitting schemes for a class of reactive systems  

Science Conference Proceedings (OSTI)

We consider the numerical time integration of a class of reaction-transport systems that are described by a set of ordinary differential equations for primary variables. In the governing equations, the terms involved may require the knowledge of secondary ... Keywords: 65L05, 80A32, Continuously stirred tank reactor, Operator splitting, Reaction-transport systems, Reduced description of reactive flows

Zhuyin Ren; Stephen B. Pope

2008-09-01T23:59:59.000Z

333

ADVANCING REACTIVE TRACER METHODS FOR MONITORING THERMAL DRAWDOWN IN GEOTHERMAL ENHANCED GEOTHERMAL RESERVOIRS  

Science Conference Proceedings (OSTI)

Reactive tracers have long been considered a possible means of measuring thermal drawdown in a geothermal system, before significant cooling occurs at the extraction well. Here, we examine the sensitivity of the proposed method to evaluate reservoir cooling and demonstrate that while the sensitivity of the method as generally proposed is low, it may be practical under certain conditions.

Mitchell A. Plummer; Carl D. Palmer; Earl D. Mattson; George D. Redden; Laurence C. Hull

2010-10-01T23:59:59.000Z

334

Topical Report on Reactivity Initiated Accident: Bases for RIA Fuel and Core Coolability Criteria  

Science Conference Proceedings (OSTI)

Revised acceptance criteria have been developed for the response of light water reactor (LWR) fuel under reactivity initiated accidents (RIA). Development of these revisions is part of an industry effort to extend burnup levels beyond currently licensed limits. The revised criteria are proposed for use in licensing burnup extensions or new fuel designs.

2002-05-22T23:59:59.000Z

335

Distributed control of reactive power flow in a radial distribution circuit with high photovoltaic penetration  

SciTech Connect

We show how distributed control of reactive power can serve to regulate voltage and minimize resistive losses in a distribution circuit that includes a significant level of photovoltaic (PV) generation. To demonstrate the technique, we consider a radial distribution circuit with a single branch consisting of sequentially-arranged residential-scale loads that consume both real and reactive power. In parallel, some loads also have PV generation capability. We postulate that the inverters associated with each PV system are also capable of limited reactive power generation or consumption, and we seek to find the optimal dispatch of each inverter's reactive power to both maintain the voltage within an acceptable range and minimize the resistive losses over the entire circuit. We assume the complex impedance of the distribution circuit links and the instantaneous load and PV generation at each load are known. We compare the results of the optimal dispatch with a suboptimal local scheme that does not require any communication. On our model distribution circuit, we illustrate the feasibility of high levels of PV penetration and a significant (20% or higher) reduction in losses.

Chertkov, Michael [Los Alamos National Laboratory; Turitsyn, Konstantin [Los Alamos National Laboratory; Backhaus, Scott [Los Alamos National Laboratory; Sule, Petr [NEW MEXICO CONSORTIUM

2009-01-01T23:59:59.000Z

336

Comparative study for EAF's reactive energy compensation methods and power factor improvement  

Science Conference Proceedings (OSTI)

In this paper is analyzing the current operating conditions of one electric arc furnace (EAF) in order to evaluate the best option to solve the energy consumption problem. Experimental results show that EAFs represent a substantial source of electric ... Keywords: electric arc furnace, flicker, harmonic analysis, improvement, power factor, reactive compensator

Deaconu Sorin Ioan; Popa Gabriel Nicolae; Tihomir Latinovic

2010-09-01T23:59:59.000Z

337

REACTIVE FLOW IN LARGE-DEFORMATION ELECTRODES OF LITHIUM-ION BATTERIES  

E-Print Network (OSTI)

8/3/2012 1 REACTIVE FLOW IN LARGE-DEFORMATION ELECTRODES OF LITHIUM-ION BATTERIES LAURENCE BRASSART;8/3/2012 2 1. Introduction In a lithium-ion battery, each electrode is a host of lithium. When the battery to 4.4 lithium atoms. By comparison, in the commonly used anodes in lithium-ion batteries made

Suo, Zhigang

338

The Reactive Light Yellow Dye Wastewater Treatment by Sewage Sludge-Based Activated Carbon  

Science Conference Proceedings (OSTI)

The paper is aim to discuss the dye wastewater treatment by sewage sludge-based adsorbent. The adsorbent derived from sewage sludge, which produced through phosphoric acid-microwave method, and commercia activated carbon (ACC) were tested in the process ... Keywords: Sewage Sludge-based Activated Carbon (ACSS), the Reactive Light Yellow, Dye Wastewater, Adsorption

Yang Lijun; Dai Qunwei

2011-02-01T23:59:59.000Z

339

Gas chromatograph-mass spectrometer (GC/MS) system for quantitative analysis of reactive chemical compounds  

DOE Patents (OSTI)

Described is a new gas chromatograph-mass spectrometer (GC/MS) system and method for quantitative analysis of reactive chemical compounds. All components of such a GC/MS system external to the oven of the gas chromatograph are programmably temperature controlled to operate at a volatilization temperature specific to the compound(s) sought to be separated and measured.

Grindstaff, Quirinus G. (Oak Ridge, TN)

1992-01-01T23:59:59.000Z

340

Synthesis and reactivity of molybdenum organometallic complexes supported by amide ligands  

E-Print Network (OSTI)

Chapter 1. Synthesis and Reactivity of Molybdenum Alkyl Complexes Supported by a Diamidoamine Ligand. The synthesis of a new diamidoamine ligand, CH3N[CH2CH2NH(3-(CF3)C6H4)]2 (H2L) is reported. Molybdenum complexes of the ...

Hock, Adam S. (Adam Scott)

2007-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Time-critical Underwater Sensor Diffusion with No Proactive Exchanges and Negligible Reactive Floods  

E-Print Network (OSTI)

Time-critical Underwater Sensor Diffusion with No Proactive Exchanges and Negligible Reactive multi-hop ad hoc routing in a scalable Underwater Sensor Network (UWSN), which is a novel network in the challenging new underwater environment. Unlike the terrestrial scenarios, on-demand flooding cannot be both

Park, Joon-Sang

342

Using reactive transport modeling to evaluate the source term at Yucca mountain  

Science Conference Proceedings (OSTI)

The conventional approach of source-term evaluation for performance assessment of nuclear waste repositories uses the dissolution rate of waste form and the solubility of pure phases of radioactive elements to constrain radionuclide concentrations. This ... Keywords: neptunium, nuclear waste, radionuclide solubility, reactive-transport modeling, secondary phases, spent nuclear fuel, uranium

Yueting Chen

2003-04-01T23:59:59.000Z

343

REACTIVITY LIFETIME. TEST RESULTS DL-S-225(T-612118A). Section I, Second Performance  

SciTech Connect

The performance, reliability, stability, and reactivity lifetime variations of the Shippingport PWR are determined under normal steady state conditions. These characteristics are studied over a period of 758 EFPH, at a power level of about 60 Mw(e). Flux-tilt corrections and plant operations during this time are described. (T.F.H.)

1959-03-01T23:59:59.000Z

344

Multicomponent reactive transport modeling at the Ratones uranium mine, Cceres (Spain)  

E-Print Network (OSTI)

management. The Ratones uranium mine was abandoned and flooded in 1974. Due to its reducing undergroundMulticomponent reactive transport modeling at the Ratones uranium mine, Cáceres (Spain) Modelación/06/05 / Accepted: 02/10/05 Abstract Flooding of abandoned mines may have a major impact in groundwater quality

Politècnica de Catalunya, Universitat

345

Uranium Tris-aryloxide Derivatives Supported by Triazacyclononane: Engendering a Reactive Uranium(III)  

E-Print Network (OSTI)

Uranium Tris-aryloxide Derivatives Supported by Triazacyclononane: Engendering a Reactive Uranium-mail: kmeyer@ucsd.edu Abstract: The synthesis and spectroscopic characterization of the mononuclear uranium complex [((ArO)3tacn)UIII (NCCH3)] is reported. The uranium(III) complex reacts with organic azides

Meyer, Karsten

346

Distributed control of reactive power flow in a radial distribution circuit with high photovoltaic penetration  

SciTech Connect

We show how distributed control of reactive power can serve to regulate voltage and minimize resistive losses in a distribution circuit that includes a significant level of photovoltaic (PV) generation. To demonstrate the technique, we consider a radial distribution circuit with a single branch consisting of sequentially-arranged residential-scale loads that consume both real and reactive power. In parallel, some loads also have PV generation capability. We postulate that the inverters associated with each PV system are also capable of limited reactive power generation or consumption, and we seek to find the optimal dispatch of each inverter's reactive power to both maintain the voltage within an acceptable range and minimize the resistive losses over the entire circuit. We assume the complex impedance of the distribution circuit links and the instantaneous load and PV generation at each load are known. We compare the results of the optimal dispatch with a suboptimal local scheme that does not require any communication. On our model distribution circuit, we illustrate the feasibility of high levels of PV penetration and a significant (20% or higher) reduction in losses.

Chertkov, Michael [Los Alamos National Laboratory; Turitsyn, Konstantin [Los Alamos National Laboratory; Backhaus, Scott [Los Alamos National Laboratory; Sule, Petr [NEW MEXICO CONSORTIUM

2009-01-01T23:59:59.000Z

347

Bulk Burning Rate in Passive Reactive Diffusion. Peter Constantin Alexander Kiselev Adam Oberman  

E-Print Network (OSTI)

Bulk Burning Rate in Passive ­ Reactive Diffusion. Peter Constantin Alexander Kiselev Adam Oberman, diffuses, and reacts according to a KPP­type nonlinear reaction. We introduce a quantity, the bulk burning­defined notion of front speed. We establish rigorous lower bounds for the bulk burning rate that are linear

Ryzhik, Lenya

348

Calculation of the proportion of reactive waste for hydrogen ignition scenario  

DOE Green Energy (OSTI)

This study was conducted as outlined in NHC Letter of Instruction 9751330 dated February 247 1997 and entitled {open_quotes}Analysis by Pacific Northwest National Laboratory to Support a Safety Assessment for Rotary Mode Core Sampling in Flammable Gas Watchlist Tanks{close_quotes}. As prescribed in this letter, the results of this study were provided to Los Alamos National Laboratory (LANL) to revise the safety assessment document. Sampling Hanford tanks with a rotary drill could result in a drill-bit overheating accident which could ignite flammable gases present in the tanks. According to calculations, an over-heated drill bit could not get hot enough to ignite the hydrogen directly. However, an overheated drill bit could ignite saltcake waste containing high concentrations of organics, and a local organics burn would achieve sufficient temperature to ignite flammable gas present in the waste. This report estimates one quantity required to evaluate this particular accident scenario; the fraction of reactive waste in the tank waste. Reactive waste is waste that contains sufficient organic carbon and a low enough moisture content to ignite when in contact with an over-heated drill bit. This report presents a methodology to calculate the proportion of reactive waste for the 100 series tanks, using sampling data from tank characterization studies. The tanks are ranked according to their reactive waste proportions, and confidence limits are assigned to the estimates.

Gao, Feng; Heasler, P.G.

1997-04-01T23:59:59.000Z

349

EV/PHEV Bidirectional Charger Assessment for V2G Reactive Power Operation  

SciTech Connect

This paper presents a summary of the available single-phase ac-dc topologies used for EV/PHEV, level-1 and -2 on-board charging and for providing reactive power support to the utility grid. It presents the design motives of single-phase on-board chargers in detail and makes a classification of the chargers based on their future vehicle-to-grid usage. The pros and cons of each different ac-dc topology are discussed to shed light on their suitability for reactive power support. This paper also presents and analyzes the differences between charging-only operation and capacitive reactive power operation that results in increased demand from the dc-link capacitor (more charge/discharge cycles and increased second harmonic ripple current). Moreover, battery state of charge is spared from losses during reactive power operation, but converter output power must be limited below its rated power rating to have the same stress on the dc-link capacitor.

Kisacikoglu, Mithat C [ORNL; Ozpineci, Burak [ORNL; Tolbert, Leon M [ORNL

2013-01-01T23:59:59.000Z

350

Study on reactive power optimization problem taking the line current as state variable  

Science Conference Proceedings (OSTI)

The math model of optimization problem is established by describing the electric power network equations as the hybrid form with node voltage and line current based on ? equivalence circuit of power equipment, there the objective function is performed ... Keywords: line current, node voltage, optimal power flow, power flow, reactive power optimization

Zhang Jinsong; Wang Chengmin; Zhang Gong; Hou Zhijian

2005-10-01T23:59:59.000Z

351

LSCF Synthesis and Syngas Reactivity over LSCF-modified Ni/YSZ Anode.  

E-Print Network (OSTI)

??Simulated coal syngas reactivity over Ni/YSZ and LSCF (La0.6Sr0.4Co0.2Fe0.8)-modified Ni/YSZ anode of SOFC (solid oxide fuel cell) was investigated in this study. The contribution of… (more)

Mirzababaei, Jelvehnaz

2011-01-01T23:59:59.000Z

352

CO{sub 2}-gasification reactivity of different carbonaceous materials at elevated temperatures  

SciTech Connect

At the atmospheric pressure and at the temperatures between 1,223 and 1,673 K, the CO{sub 2} gasification reactivity of seven different carbonaceous materials comprising coal tar pitch coke, petroleum coke, natural graphite, carbon black and three coal chars was investigated by using thermogravimetric analysis. Their crystalline structures were analyzed by X-ray diffraction (XRD). It is found that the reactivity of the chars, pitch coke and petroleum coke produced from liquid phase carbonization, is several times poorer than that of the coal chars produced from solid phase carbonization and even lower than that of natural graphite. At the same time, it is obtained that under the condition of the chemical reaction control, the apparent activation energies of the former are in the range of 135.82-174.92 kJ/mol, while those of the latter are between 89.95 kJ/mol and 110.05 kJ/mol. Besides, the reactivity of the sample has a certain correlation with the crystalline structure of the sample, i.e., the larger the fraction of the relatively better crystalline structure is, the poorer the reactivity of the sample is.

Gu, J.; Wu, S.; Wu, Y.; Gao, J. [East China University of Science and Technology, Shanghai (China)

2009-07-01T23:59:59.000Z

353

PAPER ACCEPTED TO IEEE TRANSACTIONS ON POWER SYSTEMS, Nov. 2008 1 Reactive Power and Voltage Control in Distribution  

E-Print Network (OSTI)

PAPER ACCEPTED TO IEEE TRANSACTIONS ON POWER SYSTEMS, Nov. 2008 1 Reactive Power and Voltage) problem associated with reactive power and voltage control in distribution systems to minimize daily on the number of switching operations of transformer load tap changers (LTCs) and capacitors, which are modeled

Cañizares, Claudio A.

354

Reactive Deposition of Silicon Nanowires Templated on a Stepped Nickel Surface Yi Wang and S. J. Sibener*  

E-Print Network (OSTI)

The initial stages of disilane Si2H6 reactive deposition on Ni(977) to form silicon nanowires have been examined using scanning tunneling microscopy. The effects of disilane exposure and dosing rate by reactive deposition of disilane (Si2H6) on Ni(977). At low dosing exposures, Si2H6 decomposes

Sibener, Steven

355

GE Energy Coupled Microgirid Project -University of Notre Dame -April 7, 2011 Distributive Reactive Control in Coupled Microgrids  

E-Print Network (OSTI)

Reactive Control in Coupled Microgrids Task Objectives and Approach simPower Model of MV Network CERTS Microgrid Models Reactive Control of Voltage Rise Deliverables Schedule Distributed Event-Triggered Control of Coupled Microgrids #12;Task Objectives and Approach Task will develop distributed methods to maximize

Lemmon, Michael

356

Chemical Analysis of Complex Organic Mixtures Using Reactive Nanospray Desorption Electrospray Ionization Mass Spectrometry  

SciTech Connect

Reactive nanospray desorption electrospray ionization (nano-DESI) combined with high-resolution mass spectrometry was utilized for the analysis of secondary organic aerosol produced through ozonolysis of limonene (LSOA). Previous studies showed that LSOA constituents are multifunctional compounds containing aldehyde and ketone groups. In this study, we used the selectivity of the Girard T (GT) reagent towards carbonyl compounds to examine the utility of reactive nano-DESI for the analysis of complex organic mixtures. In these experiments, 1-100 {micro}M GT solution was used as a working solvent for reactive nano-DESI analysis. Abundant products of a single addition of GT to LSOA constituents were observed at GT concentrations in excess of 10 {micro}M. We found that LSOA compounds with 18-20 carbon atoms (dimers) and 27-30 carbon atoms (trimers) react with GT through a simple addition reaction resulting in formation of the carbinolamine derivative. In contrast, reactions of GT with monomeric species result in formation of both the carbinolamine and the hydrazone derivatives. In addition, several monomers did not react with GT on the timescale of our experiment. These molecules were characterized by relatively high values of the double bond equivalent (DBE) and low oxygen content. Furthermore, because addition of a charged GT tag to a neutral molecule eliminates the discrimination against the low proton affinity compounds in the ionization process, reactive nano-DESI analysis enables quantification of individual compounds in the complex mixture. For example, we were able to estimate for the first time the amounts of dimers and trimers in the LSOA mixture. Specifically, we found that the most abundant LSOA dimer was detected at ca. 0.5 pg level and the total amount of dimers and trimers in the analyzed sample was just around 11 pg. Our results indicate that reactive nano-DESI is a valuable approach for examining the presence of specific functional groups and quantification of compounds possessing these groups in complex mixtures.

Laskin, Julia; Eckert, Peter A.; Roach, Patrick J.; Heath, Brandi S.; Nizkorodov, Sergey A.; Laskin, Alexander

2012-08-21T23:59:59.000Z

357

STOMP-ECKEChem: An Engineering Perspective on Reactive Transport in Geologic Media  

Science Conference Proceedings (OSTI)

ECKEChem (Equilibrium, Conservation, Kinetic Equation Chemistry) is a reactive transport module for the STOMP suite of multifluid subsurface flow and transport simulators that was developed from an engineering perspective. STOMP comprises a suite of operational modes that are distinguished by the solved coupled conservation equations with capabilities for a variety of subsurface applications (e.g., environmental remediation and stewardship, geologic sequestration of greenhouse gases, gas hydrate production, and oil shale production). The ECKEChem module was designed to provide integrated reactive transport capabilities across the suite of STOMP simulator operational modes. The initial application for the ECKEChem module was in the simulation of the mineralization reactions that occurred with the injection of supercritical carbon dioxide into deep Columbia River basalt formations, where it was implemented in the STOMP-CO2 simulator. The STOMP-ECKEChem solution approach to modeling reactive transport in multifluid geologic media is founded on an engineering perspective: (1) sequential non-iterative coupling between the flow and reactive transport is sufficient, (2) reactive transport can be modeled by operator splitting with local geochemistry and global transport, (3) geochemistry can be expressed as a system of coupled nonlinear equilibrium, conservation and kinetic equations, (4) a limited number of kinetic equation forms are used in geochemical practice. This chapter describes the conceptual approach to converting a geochemical reaction network into a series of equilibrium, conservation and kinetic equations, the implementation of ECKEChem in STOMP, the numerical solution approach, and a demonstration of the simulator on a complex application involving desorption of uranium from contaminated field-textured sediments.

White, Mark D.; Fang, Yilin

2012-04-04T23:59:59.000Z

358

Data:34a51fea-f6be-4efc-b190-e7cb13fb935a | Open Energy Information  

Open Energy Info (EERE)

a51fea-f6be-4efc-b190-e7cb13fb935a a51fea-f6be-4efc-b190-e7cb13fb935a No revision has been approved for this page. It is currently under review by our subject matter experts. Jump to: navigation, search Loading... 1. Basic Information 2. Demand 3. Energy << Previous 1 2 3 Next >> Basic Information Utility name: The Potomac Edison Co (West Virginia) Effective date: 2012/04/02 End date if known: Rate name: PP (Large Primary) Sector: Commercial Description: AVAILABLE to single point of delivery for balanced three-phase power loads of not less than 3,000 kilovolt-amperes (1,000 kilovolt-amperes for Customers served here under prior to July 22, 1980) at prevailing voltages as designated by Company but not less than 15,000 volts. Also available at Company standard voltages between 10,000 and 15,000 volts where Company elects to supply service by one transformation from an adjacent transmission line operated at a voltage in excess of 100,000 volts. Service shall not be available for Standby or Maintenance Service such as that required for Alternative Generation Facilities. An Electric Service Agreement shall be executed.

359

Overview on backfill materials and permeable reactive barriers for nuclear waste disposal facilities.  

SciTech Connect

A great deal of money and effort has been spent on environmental restoration during the past several decades. Significant progress has been made on improving air quality, cleaning up and preventing leaching from dumps and landfills, and improving surface water quality. However, significant challenges still exist in all of these areas. Among the more difficult and expensive environmental problems, and often the primary factor limiting closure of contaminated sites following surface restoration, is contamination of ground water. The most common technology used for remediating ground water is surface treatment where the water is pumped to the surface, treated and pumped back into the ground or released at a nearby river or lake. Although still useful for certain remediation scenarios, the limitations of pump-and-treat technologies have recently been recognized, along with the need for innovative solutions to ground-water contamination. Even with the current challenges we face there is a strong need to create geological repository systems for dispose of radioactive wastes containing long-lived radionuclides. The potential contamination of groundwater is a major factor in selection of a radioactive waste disposal site, design of the facility, future scenarios such as human intrusion into the repository and possible need for retrieving the radioactive material, and the use of backfills designed to keep the radionuclides immobile. One of the most promising technologies for remediation of contaminated sites and design of radioactive waste repositories is the use of permeable reactive barriers (PRBs). PRBs are constructed of reactive material(s) to intercept and remove the radionuclides from the water and decontaminate the plumes in situ. The concept of PRBs is relatively simple. The reactive material(s) is placed in the subsurface between the waste or contaminated area and the groundwater. Reactive materials used thus far in practice and research include zero valent iron, hydroxyapatite, magnesium oxide, and others. As the contaminant moves through the reactive material, the contaminant is either sorbed by the reactive material or chemically reacts with the material to form a less harmful substance. Because of the high risk associated with failure of a geological repository for nuclear waste, most nations favor a near-field multibarrier engineered system using backfill materials to prevent release of radionuclides into the surrounding groundwater.

Moore, Robert Charles; Hasan, Ahmed Ali Mohamed; Holt, Kathleen Caroline; Hasan, Mahmoud A. (Egyptian Atomic Energy Authority, Cairo, Egypt)

2003-10-01T23:59:59.000Z

360

Zinc Thiolate Reactivity toward Nitrogen Oxides: Insights into the Interaction of Zn[superscript 2+] with S-Nitrosothiols and Implications for Nitric Oxide Synthase  

E-Print Network (OSTI)

Zinc thiolate complexes containing N[subscript 2]S tridentate ligands were prepared to investigate their reactivity toward reactive nitrogen species, chemistry proposed to occur at the zinc tetracysteine thiolate site of ...

Kozhukh, Julia

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Preliminary investigation of actinide and xenon reactivity effects in accelerator transmutation of waste high-flux systems  

SciTech Connect

The possibility of an unstable positive reactivity growth in an accelerator transmutation of waste (ATW)-type high-flux system is investigated. While it has always been clear that xenon is an important actor in the reactivity response of a system to flux changes, it has been suggested that in very high thermal flux transuranic burning systems, a positive, unstable reactivity growth could be caused by the actinides alone. Initial system reactivity response to flux changes caused by the actinides and xenon are investigated separately. The maximum change in reactivity after a flux change caused by the effect of the changing quantities of actinides is generally at least two orders of magnitude smaller than either the positive or negative reactivity effect associated with xenon after a shutdown or startup. In any transient flux event, the reactivity response of the system to xenon will generally occlude the response caused by the actinides. The capabilities and applications of both the current actinide model and the xenon model are discussed. Finally, the need for a complete dynamic model for the high-flux fluid-fueled ATW system is addressed.

Olson, K.R.; Henderson, D.L. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Nuclear Engineering and Engineering Physics; Woosley, M.L. Jr. [Univ. of virginia, Charlottesville, VA (United States). Dept. of Mechanical, Aerospace, and Nuclear Engineering; Sailor, W.C. [Los Alamos National Lab., NM (United States)

1995-04-01T23:59:59.000Z

362

Chemically reactive species in liquids generated by atmospheric-pressure plasmas and their roles in plasma medicine  

SciTech Connect

Plasmas whose gas temperatures are close to room temperature may be generated in ambient air or a gas at atmospheric pressure with the use of low-frequency high voltage or low-power radio-frequency (RF) or microwave power applied to electrodes. Such plasmas can serve as a powerful source of free radicals and/or chemically reactive species that arise from atoms and molecules of the ambient gas. Recently use of such plasmas for medical purposes has attracted much attention as they can be implemented in possible medical devices that can cause blood coagulation, heal wounds, facilitate angiogenesis, sterilize surgical devices as well as living tissues without harming healthy cells, and selectively inactivate cancer cells. Especially of interest among reactive species generated by atmospheric-pressure plasmas (APP) are reactive oxygen species (ROS) and reactive nitrogen species (RNS) that are generated in liquid phase. Since most living tissues and cells are immersed in liquids (such as blood or culture media), reactive species generated by APPs in the gas phase are transported to the liquid phase and possibly converted to different types of reactive species therein before causing some influence on the tissues or cells. In this study, the rate equations are solved to evaluate concentrations of various reactive species in pure water that are originated by plasma reactions in atmosphere and possible effects of such species (including ROS/RNS) on living tissues and cells are discussed.

Hamaguchi, Satoshi [Center for Atomic and Molecular Technologies, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)

2013-07-11T23:59:59.000Z

363

[Reactive collisions of high-temperature systems]. [Technical progress report 1990  

DOE Green Energy (OSTI)

The object of this research is to study reactivity at superthermal collision energies using a fast neutral beam that is generated by photodetachment. Systems scheduled for initial study include basic oxygen-hydrogen reactions. Unfortunately, we can not yet report realization of this goal, but during this funding period we have made advances that are anticipated to lead to successful measurements during the next year. The parameters described below refer to the model system O + H{sub 2} {yields} OH + H. The basic design involves the collision of fast neutrals, created by photodetachment of the corresponding negative molecular ion, with a stable reactant gas in a collision cell. Products are detected by ionization and mass analysis. We are equipped to study rotational effects on reactivity by comparing results for rotational levels J = 0 and 1 of H{sub 2}. Highlights during the funding period are given in this report.

Graff, M.M.

1990-12-31T23:59:59.000Z

364

Probing Material Reactivity Using X-ray Pair Distribution Function Methods  

NLE Websites -- All DOE Office Websites (Extended Search)

Material Reactivity Using X-ray Pair Distribution Material Reactivity Using X-ray Pair Distribution Function Methods Karena W. Chapman X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, USA Understanding how advanced functional materials react and transform, at an atomic scale, is a characterization challenge with many diverse phenomena possible; components with varying particle size, morphology, and microstructure can evolve from multi-atom clusters to multi-million atom crystals. The pair distribution function (PDF) method shows great promise for providing quantitative insight such reactions. Recent advances in experimental methods, have improved the efficiency of X-ray PDF measurements, to allow time-resolved experiments with sufficient resolution to study reactions in solid

365

DIESEL OXIDATION CATALYST CONTROL OF HYDROCARBON AEROSOLS FROM REACTIVITY CONTROLLED COMPRESSION IGNITION COMBUSTION  

SciTech Connect

Reactivity Controlled Compression Ignition (RCCI) is a novel combustion process that utilizes two fuels with different reactivity to stage and control combustion and enable homogeneous combustion. The technique has been proven experimentally in previous work with diesel and gasoline fuels; low NOx emissions and high efficiencies were observed from RCCI in comparison to conventional combustion. In previous studies on a multi-cylinder engine, particulate matter (PM) emission measurements from RCCI suggested that hydrocarbons were a major component of the PM mass. Further studies were conducted on this multi-cylinder engine platform to characterize the PM emissions in more detail and understand the effect of a diesel oxidation catalyst (DOC) on the hydrocarbon-dominated PM emissions. Results from the study show that the DOC can effectively reduce the hydrocarbon emissions as well as the overall PM from RCCI combustion. The bimodal size distribution of PM from RCCI is altered by the DOC which reduces the smaller mode 10 nm size particles.

Prikhodko, Vitaly Y [ORNL; Parks, II, James E [ORNL; Barone, Teresa L [ORNL; Curran, Scott [ORNL; Cho, Kukwon [ORNL; Lewis Sr, Samuel Arthur [ORNL; Storey, John Morse [ORNL; Wagner, Robert M [ORNL

2011-01-01T23:59:59.000Z

366

Reactivity estimation and validation for the control of reactor neutronic power. Master's thesis  

SciTech Connect

From July 1986 to July 1991, a joint MIT-SNL research team developed a controller capable of safely raising reactor power by approximately five orders of magnitude in a few seconds. This controller was experimentally demonstrated on the MIT Research Reactor (MITR-II) as well as on the 'Sandia National Laboratories' Annular Core Research Reactor (ACRR). This controller's intended application is for the control of spacecraft nuclear reactors. However, it also has direct application for the control of military, commercial, and research reactors. This report is concerned with a method for enhancing the controller's performance through the development of an improved model to validate estimates of the magnitude of reactivity feedback effects. The focus is on the Doppler effect but the resulting model is applicable to other types of reactivity feedback such as that associated with the thermal effects of a hydrogen coolant.

Lasota, C.S.

1993-05-01T23:59:59.000Z

367

1 Setting Speculative and Reactive Capacities When an Early Demand Signal  

E-Print Network (OSTI)

Consider a fashion goods retailer choosing a strategy for contracting production of its products. It can 1) speculate by contracting for a certain quantity to be produced well ahead of uncertain demand at relatively low unit cost, 2) react by waiting until demand is known, and only then contracting for just the right quantity at a higher unit cost, or 3) hedge its bets by speculating on a portion of the total quantity, and reacting to demand for the rest. Using a twoproduct two-stage model, we identify the conditions under which each strategy is preferred, and determine capacity requirements. We find that fashion retailing often benefits from the dual strategy due to relatively higher obsolescence costs. But the use of the dual strategy is sensitive to the cost premium for reactive capacity and to the makeup of reactive production costs as either largely variable or fixed.

Kyle Cattani; Ely Dahan; Glen M. Schmidt

2007-01-01T23:59:59.000Z

368

Heterogeneous reactivity effects in medium- and high-enriched uranium metal-water systems  

DOE Green Energy (OSTI)

The effect of heterogeneity on reactivity of low-, medium-, and high-enriched, water-moderated uranium metal systems has been examined for various hydrogen-to-fissile (H/X) ratios using the CSAS1X sequence in SCALE and MCNP. For the calculations, an infinite array of close-packed unit cells was modeled which consisted of centered uranium metal spheres surrounded by water. The enrichments used correspond to the average enrichments of fragmented fuel plates in three proposed waste shipments from Oak Ridge National Laboratory. The analysis performed to obtain peak reactivity for each enrichment as a function of particle size and H/X ratio led to the development of the topic discussed in this paper.

Lichtenwalter, J.J.

1997-07-01T23:59:59.000Z

369

Method of extruding and packaging a thin sample of reactive material, including forming the extrusion die  

DOE Patents (OSTI)

This invention teaches a method of cutting a narrow slot in an extrusion die with an electrical discharge machine by first drilling spaced holes at the ends of where the slot will be, whereby the oil can flow through the holes and slot to flush the material eroded away as the slot is being cut. The invention further teaches a method of extruding a very thin ribbon of solid highly reactive material such as lithium or sodium through the die in an inert atmosphere of nitrogen, argon, or the like as in a glovebox. The invention further teaches a method of stamping out sample discs from the ribbon and of packaging each disc by sandwiching it between two aluminum sheets and cold welding the sheets together along an annular seam beyond the outer periphery of the disc. This provides a sample of high purity reactive material that can have a long shelf life.

Lewandowski, E.F.; Peterson, L.L.

1981-11-30T23:59:59.000Z

370

Method of extruding and packaging a thin sample of reactive material including forming the extrusion die  

DOE Patents (OSTI)

This invention teaches a method of cutting a narrow slot in an extrusion die with an electrical discharge machine by first drilling spaced holes at the ends of where the slot will be, whereby the oil can flow through the holes and slot to flush the material eroded away as the slot is being cut. The invention further teaches a method of extruding a very thin ribbon of solid highly reactive material such as lithium or sodium through the die in an inert atmosphere of nitrogen, argon or the like as in a glovebox. The invention further teaches a method of stamping out sample discs from the ribbon and of packaging each disc by sandwiching it between two aluminum sheets and cold welding the sheets together along an annular seam beyond the outer periphery of the disc. This provides a sample of high purity reactive material that can have a long shelf life.

Lewandowski, Edward F. (Westmont, IL); Peterson, Leroy L. (Joliet, IL)

1985-01-01T23:59:59.000Z

371

Apparatus and method for atmospheric pressure reactive atom plasma processing for shaping of damage free surfaces  

DOE Patents (OSTI)

Fabrication apparatus and methods are disclosed for shaping and finishing difficult materials with no subsurface damage. The apparatus and methods use an atmospheric pressure mixed gas plasma discharge as a sub-aperture polisher of, for example, fused silica and single crystal silicon, silicon carbide and other materials. In one example, workpiece material is removed at the atomic level through reaction with fluorine atoms. In this example, these reactive species are produced by a noble gas plasma from trace constituent fluorocarbons or other fluorine containing gases added to the host argon matrix. The products of the reaction are gas phase compounds that flow from the surface of the workpiece, exposing fresh material to the etchant without condensation and redeposition on the newly created surface. The discharge provides a stable and predictable distribution of reactive species permitting the generation of a predetermined surface by translating the plasma across the workpiece along a calculated path.

Carr; Jeffrey W. (Livermore, CA)

2009-03-31T23:59:59.000Z

372

Catalytic and reactive polypeptides and methods for their preparation and use  

DOE Patents (OSTI)

Catalytic and reactive polypeptides include a binding site specific for a reactant or reactive intermediate involved in a chemical reaction of interest. The polypeptides further include at least one active functionality proximate the binding site, where the active functionality is capable of catalyzing or chemically participating in the chemical reaction in such a way that the reaction rate is enhanced. Methods for preparing the catalytic peptides include chemical synthesis, site-directed mutagenesis of antibody and enzyme genes, covalent attachment of the functionalities through particular amino acid side chains, and the like. This invention was made with Government support under Grant Contract No. AI-24695, awarded by the Department of health and Human Services, and under Grant Contract No. N 00014-87-K-0256, awarded by the Office of Naval Research. The Government has certain rights in this invention.

Schultz, Peter (Oakland, CA)

1994-01-01T23:59:59.000Z

373

Examination of a PHEV Bi-Directional Charger System for V2G Reactive Power Compensation  

SciTech Connect

Plug-in hybrid electric vehicles (PHEVs) potentially have the capability to fulfill the energy storage needs of the electric grid by supplying ancillary services such as reactive power compensation. However, in order to allow bidirectional power transfer, the PHEV battery charger should be designed to manage such capability. While many different battery chargers have been available since the inception of the first electric vehicles (EVs), an on-board, conductive charger with bidirectional power transferring capability have recently drawn attention due to their inherent advantages in charging accessibility, ease of use and efficiency. In this study, a reactive power compensation case study using the inverter dc-link capacitor is given when a PHEV battery is under charging operation. Finally, the impact of providing these services on the batteries is also explained.

Kisacikoglu, Mithat C [ORNL; Ozpineci, Burak [ORNL; Tolbert, Leon M [ORNL

2010-01-01T23:59:59.000Z

374

Reactivation and operation of the large six-tesla CFFF superconducting magnet  

DOE Green Energy (OSTI)

The second MHD superconducting magnet system constructed at the Argonne National Laboratory, originally intended for use in the coal-fired plasma MHD power generation program, has been in storage at Argonne since its assembly and short-term testing a decade ago. At that time it was energized for only a few days and then decommissioned. The magnet, a 6-T dipole having an effective length of 300 cm and a tapered warm bore of 80 to 100 cm, has recently been reactivated and put into service for sea water MHD propulsion research. This report describes the technical aspects of the reactivation process, as well as the operational characterization of the reconstituted system.

Hill, D.; Libera, J.; Petrick, M.

1992-07-01T23:59:59.000Z

375

Reactivation and operation of the large six-tesla CFFF superconducting magnet  

DOE Green Energy (OSTI)

The second MHD superconducting magnet system constructed at the Argonne National Laboratory, originally intended for use in the coal-fired plasma MHD power generation program, has been in storage at Argonne since its assembly and short-term testing a decade ago. At that time it was energized for only a few days and then decommissioned. The magnet, a 6-T dipole having an effective length of 300 cm and a tapered warm bore of 80 to 100 cm, has recently been reactivated and put into service for sea water MHD propulsion research. This report describes the technical aspects of the reactivation process, as well as the operational characterization of the reconstituted system.

Hill, D.; Libera, J.; Petrick, M.

1992-01-01T23:59:59.000Z

376

TOUGHREACT-A simulation program for non-isothermal multiphase reactive geochemical transport in variably saturated geologic media: Applications to geothermal injectivity and CO2 geological sequestration  

Science Conference Proceedings (OSTI)

TOUGHREACT is a numerical simulation program for chemically reactive non-isothermal flows of multiphase fluids in porous and fractured media. The program was written in Fortran 77 and developed by introducing reactive geochemistry into the multiphase ... Keywords: CO2 geologic sequestration, Clay swelling, Geochemical transport, Hydrothermal systems, Injectivity enhancement, Mineral scaling, Mineral trapping, Reactive fluid flow, Saline aquifer, TOUGHREACT

Tianfu Xu; Eric Sonnenthal; Nicolas Spycher; Karsten Pruess

2006-03-01T23:59:59.000Z

377

Structure formation upon reactive direct current magnetron sputtering of transition metal oxide films  

Science Conference Proceedings (OSTI)

A comparative study of reactive direct current magnetron sputtering for different transition metal oxides reveals crystalline films at room temperature for group 4 and amorphous films for groups 5 and 6. This observation cannot be explained by the known growth laws and is attributed to the impact of energetic particles, originating from the oxidized target, on the growing film. This scenario is supported by measured target characteristics, the evolution of deposition stress of the films, and the observed backsputtering.

Ngaruiya, J.M.; Kappertz, O.; Mohamed, S.H.; Wuttig, M. [I. Physikalisches Institut der RWTH Aachen, D-52056 Aachen, Germany and Jomo Kenyatta University of Agriculture and Technology, Box 62000 Nairobi (Kenya); I. Physikalisches Institut der RWTH Aachen, D-52056 Aachen (Germany)

2004-08-02T23:59:59.000Z

378

Three-dimensional model for multi-component reactive transport with variable density groundwater flow  

Science Conference Proceedings (OSTI)

PHWAT is a new model that couples a geochemical reaction model (PHREEQC-2) with a density-dependent groundwater flow and solute transport model (SEAWAT) using the split-operator approach. PHWAT was developed to simulate multi-component reactive transport ... Keywords: Cation exchange, Coastal groundwater flow and chemical transport/reaction, Density-dependent flow, MODFLOW, MT3DMS, PHREEQC-2, PHWAT, SEAWAT, Seawater intrusion, Snow-plough effect

X. Mao; H. Prommer; D. A. Barry; C. D. Langevin; B. Panteleit; L. Li

2006-05-01T23:59:59.000Z

379

Pore structure and reactivity changes in hot coal gas desulfurization sorbents  

Science Conference Proceedings (OSTI)

The primary objective of the project was the investigation of the pore structure and reactivity changes occurring in metal/metal oxide sorbents used for desulfurization of hot coal gas during sulfidation and regeneration, with particular emphasis placed on the effects of these changes on the sorptive capacity and efficiency of the sorbents. Commercially available zinc oxide sorbents were used as model solids in our experimental investigation of the sulfidation and regeneration processes.

Sotirchos, S.V.

1991-05-01T23:59:59.000Z

380

Hierarchy of local chemical reactivity indices originated from a local energy  

E-Print Network (OSTI)

The traditional way of defining a local measure of chemical hardness has several drawbacks, which undermine the applicability of that local hardness concept. We propose a new approach to this problem, by originating a local chemical potential, a corresponding local hardness, and local hyperhardnesses, from a local energy concept. A chemical potential kernel is also defined, by which a recently proposed alternative local chemical potential and local hardness concept can also be incorporated into this scheme of local reactivity indices.

Gal, Tamas

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Residual carbon from pulverized coal fired boilers 1: Size distribution and combustion reactivity  

Science Conference Proceedings (OSTI)

The amount of residual, or unburned, carbon in fly ash is an important concern in the design and operation of pulverized coal-fired boilers. Char oxidation is the slowest step in the coal combustion process, and the rate at which this heterogeneous reaction-proceeds has an important effect on the degree of carbon burnout. There is an extensive literature on char combustion kinetics based on data in the early and intermediate stages of carbon conversion. A critical fundamental question is whether the small fraction of the fuel carbon that passes unreacted through a boiler is representative of the char during the main portion of the combustion process. This article addresses that question through a detailed characterization of eight carbon-containing fly ash samples acquired from commercial-scale combustion systems. The fly ash characterization included measurement-of joint carbon/size distribution and determination.of the combustion reactivity of the residual carbon. To minimize mineral matter interactions in the reactivity tests, the technique of incipient fluidization was developed for separation of carbon-rich extracts from the inorganic portion of the fly ash. Reactivity measurements were made at 1400--1800 K to represent conditions in pulverized coal fired boilers. Measurements were also made at 700--1100 K to. minimize transport effects and isolate the influence of char chemistry and microstructure. In both temperature regimes, the residual carbon extracts. were significantly less reactive than chars extracted from a laboratory-scale laminar flow reactor in the early-to-intermediate stages of combustion. It is concluded that the boiler environment deactivates chars, making high carbon burnout more difficult to achieve than is predicted by existing char combustion kinetic models that were developed from data on the laboratory chars. Finally, the results are used to discuss potential char deactivation mechanisms, both thermal and oxidative, in coal-fired boilers.

Hurt, R.H. [Sandia National Labs., Livermore, CA (United States); Gibbins, J.R. [Imperial Coll. of Science, Technology and Medicine, London (United Kingdom). Dept. of Mechanical Engineering

1994-08-01T23:59:59.000Z

382

FirstEnergy Uses EPRI Interregional Reactive Power Management Framework to Help Improve Transmission Voltage Stability  

Science Conference Proceedings (OSTI)

FirstEnergy teamed with EPRI and Powertech Labs to develop a practical, automated method for identifying areas prone to voltage instability due to a lack of reactive power reserves. Power system designers and operational planning engineers can use the new method to evaluate the performance of various power system designs or configurations with regard to susceptibility to voltage instability, determine weak areas requiring special remediation, and maximize the efficient use of assets by determining the mi...

2008-08-19T23:59:59.000Z

383

Trends vs. reactor size of passive reactivity shutdown and control performance  

SciTech Connect

The focus of the US advanced reactor program since the cancellation of CRBR has been on inherent safety and cost reduction. The notion is to so design the reactor that in the event of an off normal condition, it brings itself to a safe shutdown condition and removes decay heat by reliance on ''inherent processes'' i.e., without reliance on devices requiring switching and outside sources of power. Such a reactor design would offer the potential to eliminate costly ''Engineered Safety Features,'' to lower capital costs, and to assuage public unease concerning reactor safety. For LMR concepts, the goal of passive reactivity shutdown has been approached in the US by designing the reactors for favorable relationships among the power, power/flow, and inlet temperature coefficients of reactivity, for high internal conversion ratio (yielding small burnup control swing), and for a primary pump coastdown time appropriately matched to the delayed neutron hold back of power decay upon negative reactivity input. The use of sodium bonded metallic fuel pins has facilitated the achievement of the passive shutdown design goals as a consequence of their high thermal conductivity and high effective heavy metal density. Alternately, core designs based on derated oxide pins may be able to achieve the passive shutdown features at the cost of larger core volume and increased initial fissile inventory. 8 refs., 12 figs., 1 tab.

Wade, D.C.; Fujita, E.K.

1988-01-01T23:59:59.000Z

384

Reactive Power Laboratory: Synchronous Condenser Testing&Modeling Results - Interim Report  

Science Conference Proceedings (OSTI)

The subject report documents the work carried out by Oak Ridge National Laboratory (ORNL) during months 5-7 (May-July 2005) of a multi-year research project. The project has the overall goal of developing methods of incorporating distributed energy (DE) that can produce reactive power locally and for injecting into the distribution system. The objective for this new type of DE is to be able to provide voltage regulation and dynamic reactive power reserves without the use of extensive communication and control systems. The work performed over this three-month period focused on four aspects of the overall objective: (1) characterization of a 250HP (about 300KVAr) synchronous condenser (SC) via test runs at the ORNL Reactive Power Laboratory; (2) development of a data acquisition scheme for collecting the necessary voltage, current and power readings at the synchronous condenser and on the distribution system; (3) development of algorithms for analyzing raw test data from the various test runs; and (4) validation of a steady-state model for the synchronous condenser via the use of a commercial software package to study its effects on the ORNL 13.8/2.4kV distribution network.

Henry, SD

2005-09-27T23:59:59.000Z

385

In situ formation of magnetite reactive barriers in soil for waste stabilization  

DOE Patents (OSTI)

Reactive barriers containing magnetite and methods for making magnetite reactive barriers in situ in soil for sequestering soil contaminants including actinides and heavy metals, organic materials, iodine and technetium are disclosed. According to one embodiment, a two-step reagent introduction into soil takes place. In the first step, free oxygen is removed from the soil by separately injecting into the soil aqueous solutions of iron (II) salt, for example FeCl.sub.2, and base, for example NaOH or NH.sub.3 in about a 1:1 volume ratio. Then, in the second step, similar reagents are injected a second time (however, according to about a 1:2 volume ratio, iron to salt) to form magnetite. The magnetite formation is facilitated, in part, due to slow intrusion of oxygen into the soil from the surface. The invention techniques are suited to injection of reagents into soil in proximity to a contamination plume or source allowing in situ formation of the reactive barrier at the location of waste or hazardous material. Mixing of reagents to form. precipitate is mediated and enhanced through movement of reagents in soil as a result of phenomena including capillary action, movement of groundwater, soil washing and reagent injection pressure.

Moore, Robert C. (Edgewood, NM)

2003-01-01T23:59:59.000Z

386

On-line reactive power compensation schemes for unbalanced three phase four wire distribution feeders  

Science Conference Proceedings (OSTI)

A new reactive power compensation method is developed to reduce the negative and zero sequence components of load currents and to improve the load bus power factor of unbalanced three-phase four-wire distribution feeders. Negative and zero sequences currents may cause additional losses and damages to power systems. Load compensation at the load bus is an effective method to eliminate those undesired sequence currents. The compensation technique uses a Y-connected and a [Delta]-connected static reactive power compensators to give a different amount of reactive power compensation to each phase. The compensation formulas are very suitable for on-line control by measuring phase voltages and currents in the real time. The compensation effect can also be achieved even if one leg of the SVCs is out of service. In addition to balancing effect and power factor improvement at the load bus, the SVCs can also be used to support the load bus voltage and to maintain the substation feeder at unity powder factor. Digital simulations are made with the load data measured from an 11.4kV secondary substation feeder.

Sanyi Lee; Chijui Wu (National Taiwan Inst. of Tech., Taipei (Taiwan, Province of China). Dept. of Electrical Engineering)

1993-10-01T23:59:59.000Z

387

GUINEVERE experiment: Kinetic analysis of some reactivity measurement methods by deterministic and Monte Carlo codes  

Science Conference Proceedings (OSTI)

The GUINEVERE experiment (Generation of Uninterrupted Intense Neutrons at the lead Venus Reactor) is an experimental program in support of the ADS technology presently carried out at SCK-CEN in Mol (Belgium). In the experiment a modified lay-out of the original thermal VENUS critical facility is coupled to an accelerator, built by the French body CNRS in Grenoble, working in both continuous and pulsed mode and delivering 14 MeV neutrons by bombardment of deuterons on a tritium-target. The modified lay-out of the facility consists of a fast subcritical core made of 30% U-235 enriched metallic Uranium in a lead matrix. Several off-line and on-line reactivity measurement techniques will be investigated during the experimental campaign. This report is focused on the simulation by deterministic (ERANOS French code) and Monte Carlo (MCNPX US code) calculations of three reactivity measurement techniques, Slope ({alpha}-fitting), Area-ratio and Source-jerk, applied to a GUINEVERE subcritical configuration (namely SC1). The inferred reactivity, in dollar units, by the Area-ratio method shows an overall agreement between the two deterministic and Monte Carlo computational approaches, whereas the MCNPX Source-jerk results are affected by large uncertainties and allow only partial conclusions about the comparison. Finally, no particular spatial dependence of the results is observed in the case of the GUINEVERE SC1 subcritical configuration. (authors)

Bianchini, G.; Burgio, N.; Carta, M. [ENEA C.R. CASACCIA, via Anguillarese, 301, 00123 S. Maria di Galeria Roma (Italy); Peluso, V. [ENEA C.R. BOLOGNA, Via Martiri di Monte Sole, 4, 40129 Bologna (Italy); Fabrizio, V.; Ricci, L. [Univ. of Rome La Sapienza, C/o ENEA C.R. CASACCIA, via Anguillarese, 301, 00123 S. Maria di Galeria Roma (Italy)

2012-07-01T23:59:59.000Z

388

DOE/EA-1310: Finding of No Significant Impact for the Decontamination and Dismantlement of the Advanced Reactivity Measurement Facility and Couples Fast Reactivity Measurements Facility at the Idaho National Engineering and Environmental Laboratory  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

FINDING OF NO SIGNIFICANT IMPACT FOR THE DECONTAMINATION AND FINDING OF NO SIGNIFICANT IMPACT FOR THE DECONTAMINATION AND DISMANTLEMENT OF THE ADVANCED REACTIVITY MEASUREMENT FACILITY AND COUPLED FAST REACTIVITY MEASUREMENTS FACILITY AT THE IDAHO NATIONAL ENGINEERING AND ENVIRONMENTAL LABORATORY Agency: U. S. Department of Energy (DOE) Action: Finding of No Significant Impact (FONSI) Summary: The DOE prepared a Draft Environmental Assessment (EA) for the proposed "Decontamination and Dismantlement of the Advanced Reactivity Measurement Facility and Coupled Fast Reactivity Measurement Facility at the Idaho National Engineering and Environmental Laboratory" (DOE/EA-1310). The EA was prepared in accordance with the Council on Environmental Quality (CEQ) Regulations for implementing the National Environmental Policy Act (NEPA) (40 CFR 1500-1508), and the

389

Microvascular lesions and blood flow in rodent cortex  

E-Print Network (OSTI)

Pixel Clock Rate', 'zstep','Z-Step Size', 'scan_volts','Scan Volts', 'x_scan_volts', 'X scan PTP (volts)', 'y_scan_volts', 'Y scan

Nishimura, Nozomi

2006-01-01T23:59:59.000Z

390

Improved Positive Electrode Materials for Li-ion Batteries  

E-Print Network (OSTI)

could double Chevy Volt battery capacity. ” http://could-double-chevy-volt-battery-capacity/chevy-volt3-4/; “Volt’s Battery Capacity Could Double. ” http://

Conry, Thomas Edward

2012-01-01T23:59:59.000Z

391

Advancing Reactive Tracer Methods for Measurement of Thermal Evolution in Geothermal Reservoirs: Final Report  

DOE Green Energy (OSTI)

The injection of cold fluids into engineered geothermal system (EGS) and conventional geothermal reservoirs may be done to help extract heat from the subsurface or to maintain pressures within the reservoir (e.g., Rose et al., 2001). As these injected fluids move along fractures, they acquire heat from the rock matrix and remove it from the reservoir as they are extracted to the surface. A consequence of such injection is the migration of a cold-fluid front through the reservoir (Figure 1) that could eventually reach the production well and result in the lowering of the temperature of the produced fluids (thermal breakthrough). Efficient operation of an EGS as well as conventional geothermal systems involving cold-fluid injection requires accurate and timely information about thermal depletion of the reservoir in response to operation. In particular, accurate predictions of the time to thermal breakthrough and subsequent rate of thermal drawdown are necessary for reservoir management, design of fracture stimulation and well drilling programs, and forecasting of economic return. A potential method for estimating migration of a cold front between an injection well and a production well is through application of reactive tracer tests, using chemical whose rate of degradation is dependent on the reservoir temperature between the two wells (e.g., Robinson 1985). With repeated tests, the rate of migration of the thermal front can be determined, and the time to thermal breakthrough calculated. While the basic theory behind the concept of thermal tracers has been understood for some time, effective application of the method has yet to be demonstrated. This report describes results of a study that used several methods to investigate application of reactive tracers to monitoring the thermal evolution of a geothermal reservoir. These methods included (1) mathematical investigation of the sensitivity of known and hypothetical reactive tracers, (2) laboratory testing of novel tracers that would improve method sensitivity, (3) development of a software tool for design and interpretation of reactive tracer tests and (4) field testing of the reactive tracer temperature monitoring concept.

Mitchell A. Plummer; Carl D. Palmer; Earl D. Mattson; Laurence C. Hull; George D. Redden

2011-07-01T23:59:59.000Z

392

Subsurface Transport Over Reactive Multiphases (STORM): A general, coupled, nonisothermal multiphase flow, reactive transport, and porous medium alteration simulator, Version 2 user's guide  

Science Conference Proceedings (OSTI)

The Hanford Site, in southeastern Washington State, has been used extensively to produce nuclear materials for the US strategic defense arsenal by the Department of Energy (DOE) and its predecessors, the US Atomic Energy Commission and the US Energy Research and Development Administration. A large inventory of radioactive and mixed waste has accumulated in 177 buried single- and double shell tanks. Liquid waste recovered from the tanks will be pretreated to separate the low-activity fraction from the high-level and transuranic wastes. Vitrification is the leading option for immobilization of these wastes, expected to produce approximately 550,000 metric tons of Low Activity Waste (LAW) glass. This total tonnage, based on nominal Na{sub 2}O oxide loading of 20% by weight, is destined for disposal in a near-surface facility. Before disposal of the immobilized waste can proceed, the DOE must approve a performance assessment, a document that described the impacts, if any, of the disposal facility on public health and environmental resources. Studies have shown that release rates of radionuclides from the glass waste form by reaction with water determine the impacts of the disposal action more than any other independent parameter. This report describes the latest accomplishments in the development of a computational tool, Subsurface Transport Over Reactive Multiphases (STORM), Version 2, a general, coupled non-isothermal multiphase flow and reactive transport simulator. The underlying mathematics in STORM describe the rate of change of the solute concentrations of pore water in a variably saturated, non-isothermal porous medium, and the alteration of waste forms, packaging materials, backfill, and host rocks.

DH Bacon; MD White; BP McGrail

2000-03-07T23:59:59.000Z

393

Efficient and Reliable Reactive Power Supply and Consumption --Insights from an Integrated Program of Engineering and EconomicResearch  

Science Conference Proceedings (OSTI)

In 2005, the Federal Energy Regulatory Commission (FERC) began discussing regulatory policy for reactive-power procurement and pricing in competitive electricity markets. This paper summarizes findings from a unique, interdisciplinary program of public-interest research that lays a formal foundation for evaluating aspects of FERC staff recommendations and offers early insights that should be useful in guiding policy implementation, specifically by: (1) clarifying the consumers and economic characteristics of reactive power as a basis for creating incentives to appropriately price it, (2) defining specific challenges in creating a competitive market for reactive power as well as new tools needed to help ensure such a market functions efficiently, and (3) demonstrating the importance of accounting for the physical characteristics of the transmission network in planning for reactive power and avoiding the exercise of market power by suppliers.

Thomas, Robert J.; Mount, Timothy D.; Schuler, Richard; Schulze,William; Zimmerman, Ray; Alvarado, Fernando; Lesieutre, Bernard C.; Overholt, Philip N.; Eto, Joseph H.

2008-01-01T23:59:59.000Z

394

Comparison of approaches for simulating reactive solute transport involving organic degradation reactions by multiple terminal electron acceptors  

Science Conference Proceedings (OSTI)

Reactive solute transport models are useful tools for analyzing complex geochemical behavior resulting from biodegradation of organic compounds by multiple terminal electron acceptors (TEAPs). The usual approach of simulating the reactions of multiple ... Keywords: biogeochemistry, groundwater, hydrogen, monod kinetics, thermodynamics

Gary P. Curtis

2003-04-01T23:59:59.000Z

395

Hybrid high direct current circuit interrupter  

DOE Patents (OSTI)

A device and a method are disclosed for interrupting very high direct currents (greater than 100,000 amperes) and simultaneously blocking high voltages (greater than 600 volts). The device utilizes a mechanical switch to carry very high currents continuously with low loss and a silicon controlled rectifier (SCR) to bypass the current around the mechanical switch while its contacts are separating. A commutation circuit, connected in parallel with the SCR, turns off the SCR by utilizing a resonant circuit to divert the SCR current after the switch opens. 7 figs.

Rockot, J.H.; Mikesell, H.E.; Jha, K.N.

1998-08-11T23:59:59.000Z

396

Hybrid high direct current circuit interrupter  

DOE Patents (OSTI)

A device and a method for interrupting very high direct currents (greater than 100,000 amperes) and simultaneously blocking high voltages (greater than 600 volts). The device utilizes a mechanical switch to carry very high currents continuously with low loss and a silicon controlled rectifier (SCR) to bypass the current around the mechanical switch while its contacts are separating. A commutation circuit, connected in parallel with the SCR, turns off the SCR by utilizing a resonant circuit to divert the SCR current after the switch opens.

Rockot, J.H.; Mikesell, H.E.; Jha, K.N.

1996-12-31T23:59:59.000Z

397

High Power, High Voltage FETs in Linear Applications: A User's Perspective  

SciTech Connect

The specifications of the current crop of highpower, high-voltage field-effect transistors (FETs) can lure a designer into employing them in high-voltage DC equipment. Devices with extremely low on-resistance and very high power ratings are available from several manufacturers. However, our experience shows that high-voltage, linear operation of these devices at near-continuous duty can present difficult reliability challenges at stress levels well-below their published specifications. This paper chronicles the design evolution of a 600 volt, 8 ampere shunt regulator for use with megawatt-class radio transmitters, and presents a final design that has met its reliability criteria.

N. Greenough, E. Fredd, S. DePasquale

2009-09-21T23:59:59.000Z

398

Definition: System Operating Limit | Open Energy Information  

Open Energy Info (EERE)

Operating Limit Operating Limit Jump to: navigation, search Dictionary.png System Operating Limit The value (such as MW, MVar, Amperes, Frequency or Volts) that satisfies the most limiting of the prescribed operating criteria for a specified system configuration to ensure operation within acceptable reliability criteria. System Operating Limits are based upon certain operating criteria. These include, but are not limited to: Facility Ratings (Applicable pre- and post- Contingency equipment or facility ratings), Transient Stability Ratings (Applicable pre- and post-Contingency Stability Limits), Voltage Stability Ratings (Applicable pre- and post- Contingency Voltage Stability), System Voltage Limits (Applicable pre- and post- Contingency Voltage Limits)[1] Also Known As SOL

399

Tips on Homeowner Education | ornl.gov  

NLE Websites -- All DOE Office Websites (Extended Search)

In Reference In Reference Tips on Homeowner Education November 22, 2013 Figure 16. How will a new homeowner be able to navigate and successfully interact with the advanced systems of a high performance home? Pictured is the Mike and Deborah Overmyer Residence in Golden, Colorado; Designer: Dr. Phil Tabb, Boulder Architect; Style: 3-story mountain contemporary; Year built: 1997, 2480 square feet; Utility: no utility bills, off utility grid. Features: photovoltaic powered house; house is over a mile to the nearest power line; 14 Shell M75 photovoltaic panels; mounting of PV panels provides for changing the tilt angle; power at a nominal 24 volts runs through an Amanda Power Technology charge controller and to the battery bank; twenty 6 volt 220 ampere-hour Trojan T-105 batteries connected 4 in

400

Atomistic Simulations of Chemical Reactivity of TATB Under Thermal and Shock Conditions  

SciTech Connect

The study of chemical transformations that occur at the reactive shock front of energetic materials provides important information for the development of predictive models at the grain-and continuum scales. A major shortcoming of current high explosives models is the lack of chemical kinetics data of the reacting explosive in the high pressure and temperature regimes. In the absence of experimental data, long-time scale atomistic molecular dynamics simulations with reactive chemistry become a viable recourse to provide an insight into the decomposition mechanism of explosives, and to obtain effective reaction rate laws. These rates can then be incorporated into thermo-chemical-hydro codes (such as Cheetah linked to ALE3D) for accurate description of the grain and macro scales dynamics of reacting explosives. In this talk, I will present quantum simulations of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) crystals under thermal decomposition (high density and temperature) and shock compression conditions. This is the first time that condensed phase quantum methods have been used to study the chemistry of insensitive high explosives. We used the quantum-based, self-consistent charge density functional tight binding method (SCC{_}DFTB) to calculate the interatomic forces for reliable predictions of chemical reactions, and to examine electronic properties at detonation conditions for a relatively long time-scale on the order of several hundreds of picoseconds. For thermal decomposition of TATB, we conducted constant volume-temperature simulations, ranging from 0.35 to 2 nanoseconds, at {rho} = 2.87 g/cm{sup 3} at T = 3500, 3000, 2500, and 1500 K, and {rho} = 2.9 g/cm{sup 3} and 2.72 g/cm{sup 3}, at T = 3000 K. We also simulated crystal TATB's reactivity under steady overdriven shock compression using the multi-scale shock technique. We conducted shock simulations with specified shock speeds of 8, 9, and 10 km/s for up to 0.43 ns duration, enabling us to track the reactivity of TATB well into the formation of several stable gas products, such as H{sub 2}O, N{sub 2}, and CO{sub 2}. Although complex chemical transformations are occurring continuously in the dynamical, high temperature, reactive environment of our simulations, a simple overall scheme for the decomposition of TATB emerges: Water is the earliest decomposition products to form, followed by a polymerization (or condensation) process in which several TATB remaining fragments are joined together, initiating the early step in the formation of high-nitrogen clusters, along with stable products such as N{sub 2} and CO{sub 2}. Remarkably, these clusters with high concentration of carbon and nitrogen (and little oxygen) remain dynamically stable for the remaining period of the simulations. Our simulations, thus, reveal a hitherto unidentified region of high concentrations of nitrogen-rich heterocyclic clusters in reacting TATB, whose persistence impede further reactivity towards final products of fluid N{sub 2} and solid carbon. These simulations also predict significant populations of charged species such as NCO{sup -}, H{sup +}, OH{sup -}, H{sub 3}O{sup +}, and O{sup -2}, the first such observation in a reacting explosive. Finally, A reduced four steps, global reaction mechanism with Arrhenius kinetic rates for the decomposition of TATB, along with comparative Cheetah decomposition kinetics at various temperatures has been constructed and will be discussed.

Manaa, M R; Reed, E J; Fried, L E

2009-09-23T23:59:59.000Z

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401

Property:OpenEI/UtilityRate/DemandReactivePowerCharge | Open Energy  

Open Energy Info (EERE)

DemandReactivePowerCharge DemandReactivePowerCharge Jump to: navigation, search This is a property of type Number. Pages using the property "OpenEI/UtilityRate/DemandReactivePowerCharge" Showing 25 pages using this property. (previous 25) (next 25) 0 00b7ccdc-c7e0-40d2-907f-acb6ae828292 + 0.25 + 00e0b930-90c6-43c2-971a-91dade33f76a + 0.32 + 00e2a43f-6844-417a-b459-edf32d33b051 + 0.0092 + 00fb7dca-d0a6-4b11-b7de-791c2fb9f2e1 + 2.7 + 01a64840-7edc-4193-8073-ed5604e098ca + 0.83 + 035f3d22-3650-47cc-a427-bb35170db128 + 0.3 + 042f06f4-6a5b-424f-a31f-8e1c5a838700 + 0.27 + 0479cd85-894d-412b-b2ce-3b96912e9014 + 0.2 + 04bab597-fe1e-4507-8d90-144980aeba73 + 0.3 + 05211bd7-b6d3-425c-9f96-0845b7828c3c + 0.27 + 052fbe23-ac02-4195-b76d-e572cc53f669 + 0.68 + 05490683-8158-4d2f-ad96-66d5e4980890 + 0.25 +

402

Reactivity and stability of platinum and platinum alloy catalysts toward the oxygen reduction reaction  

E-Print Network (OSTI)

Density functional theory (DFT) is used to study the reactivity of Pt and Pt-M (M: Pd, Co, Ni, V, and Rh) alloy catalysts towards the oxygen reduction reaction (ORR) as a function of the alloy overall composition and surface atomic distribution and compared to that on pure Pt surfaces. Reactivity is evaluated on the basis of the adsorption strength of oxygenated compounds which are intermediate species of the four-electron oxygen reduction reaction, separating the effect of the first electron-proton transfer from that of the three last electron-proton transfer steps. It is found that most homogeneous distribution PtxM catalysts thermodynamically favor the dissociation of adsorbed OOH in comparison with pure Platinum and adsorb strongly O and OH due to the strong oxyphilicity of the M elements. On the other hand, in all cases skin Platinum surfaces catalysts do not favor the dissociation of adsorbed OOH and do favor the reduction of M-O and M-OH with respect to Platinum. Considering the overall pathway of the reactions to catalyze the ORR most of the skin Platinum monolayer catalysts provide more negative free energy changes and should behave at least in a similar way than Platinum in following order: Pt3V (skin Pt) > Pt3Co (skin Pt) > Pt3Ni (skin Pt) > Pt > PtPd (skin) > Pt4Rh (skin Pt) > PtPd3 (skin ). In all cases, the reactivity is shown to be not only sensitive to the overall composition of the catalyst, but most importantly to the surface atomic distribution. Proposed electrochemical dissolution reactions of the catalyst atoms are also analyzed for the ORR catalysts, by computing the free energy changes of Platinum and bimetallic Pt-X (X: Co, Pd, Ni, and Rh) catalysts. It is found that Platinum is thermodynamically more stable than Pt-alloys in Pt3Co, Pt3Pd, Pt3Ni and Pt4Rh.

Calvo, Sergio Rafael

2007-12-01T23:59:59.000Z

403

Reactivity Accountability Attributed to Reflector Poisons in the High Flux Isotope Reactor  

Science Conference Proceedings (OSTI)

The objective of this study is to develop a methodology to predict the reactivity impact as a function of outage time between cycles of 3He, 6Li, and other poisons in the High Flux Isotope Reactor s (HFIR) beryllium reflector. The reactivity worth at startup of the HFIR has been incorrectly predicted in the past after the reactor has been shut-down for long periods of time. The incorrect prediction was postulated to be due to the erroneous calculation of 3He buildup in the beryllium reflector. It is necessary to develop a better estimate of the start-of-cycle symmetric critical control element positions since if the estimated and actual symmetrical critical control element positions differ by more than $1.55 in reactivity (approximately one-half inch in control element startup position), HFIR is to be shutdown and a technical evaluation is performed to resolve the discrepancy prior to restart. 3He is generated and depleted during operation, but during an outage, the depletion of 3He ceases because it is a stable isotope. 3He is born from the radioactive decay of tritium, and thus the concentration of 3He increases during shutdown. SCALE, specifically the TRITON and CSAS5 control modules including the KENO V.A, COUPLE, and ORIGEN functional modules were utilized in this study. An equation relating the down time (td) to the change in symmetric control element position was generated and validated against measurements for approximately 40 HFIR operating cycles. The newly-derived correlation was shown to improve accuracy of predictions for long periods of down time.

Chandler, David [ORNL; Maldonado, G Ivan [ORNL; Primm, Trent [ORNL

2009-12-01T23:59:59.000Z

404

Dynamics of confined reactive water in Smectic clay-zeolite composites.  

SciTech Connect

The dynamics of water confined to mesoporous regions in minerals such as swelling clays and zeolites is fundamental to a wide range of resource management issues impacting many processes on a global scale, including radioactive waste containment, desalination, and enhanced oil recovery. Large-scale atomic models of freely diffusing multilayer smectite particles at low hydration confined in a silicalite cage are used to investigate water dynamics in the composite environment with the ReaxFF reactive force field over a temperature range of 300 647 K. The reactive capability of the force field enabled a range of relevant surface chemistry to emerge, including acid/base equilibria in the interlayer calcium hydrates and silanol formation on the edges of the clay and inner surface of the zeolite housing. After annealing, the resulting clay models exhibit both mono- and bilayer hydration structures. Clay surface hydration redistributed markedly and yielded to silicalite water loading. We find that the absolute rates and temperature dependence of water dynamics compare well to neutron scattering data and pulse field gradient measures from relevant samples of Ca-montmorillonite and silicalite, respectively. Within an atomistic, reactive context, our results distinguish water dynamics in the interlayer Ca(OH)2 nH2O environment from water flowing over the clay surface, and from water diffusing within silicalite. We find that the diffusion of water when complexed to Ca hydrates is considerably slower than freely diffusing water over the clay surface, and the reduced mobility is well described by a difference in the Arrhenius pre-exponential factor rather than a change in activation energy.

Pitman, Michael C. [IBM Watson Research Center, Yorktown Heights, NY; Van Duin, Adri C. T. [Pennsylvania State University, University Park, PA

2012-01-01T23:59:59.000Z

405

Dynamics of confined reactive water in smectite clay-zeolite composites  

Science Conference Proceedings (OSTI)

The dynamics of water confined to mesoporous regions in minerals such as swelling clays and zeolites is fundamental to a wide range of resource management issues impacting many processes on a global scale, including radioactive waste containment, desalination, and enhanced oil recovery. Large-scale atomic models of freely diffusing multilayer smectite particles at low hydration confined in a silicalite cage are used to investigate water dynamics in the composite environment with the ReaxFF reactive force field over a temperature range of 300 647 K. The reactive capability of the force field enabled a range of relevant surface chemistry to emerge, including acid/base equilibria in the interlayer calcium hydrates and silanol formation on the edges of the clay and inner surface of the zeolite housing. After annealing, the resulting clay models exhibit both mono- and bilayer hydration structures. Clay surface hydration redistributed markedly and yielded to silicalite water loading. We find that the absolute rates and temperature dependence of water dynamics compare well to neutron scattering data and pulse field gradient measures from relevant samples of Ca-montmorillonite and silicalite, respectively. Within an atomistic, reactive context, our results distinguish water dynamics in the interlayer Ca(OH)2 nH2O environment from water flowing over the clay surface, and from water diffusing within silicalite. We find that the diffusion of water when complexed to Ca hydrates is considerably slower than freely diffusing water over the clay surface, and the reduced mobility is well described by a difference in the Arrhenius pre-exponential factor rather than a change in activation energy.

Pitman, Michael C. [IBM Watson Research Center, Yorktown Heights, NY; Van Duin, Adri C. T. [Pennsylvania State University, University Park, PA

2012-01-01T23:59:59.000Z

406

Psychophysiological Reactivity to Self and Model Images in an Upward Social Comparison Manipulation  

E-Print Network (OSTI)

The current study examined affective reactivity to oneself in an upward socialcomparison manipulation using autonomic physiological responses. Study I was conducted to select images of thin and average size models used to elicit a social comparison process for Study II. For Study II, thirty-two female undergraduate students had their startle reflex and skin conductance responses recorded while viewing images of themselves presented adjacent to thin or average size models. Participants also viewed positive, negative, and neutral affect images to test our experimental manipulation of Peter Lang’s startle paradigm. Following the visual presentation, participants used the SAM scale to rate each image along the dimensions of valence, arousal, dominance, body satisfaction, and attractiveness. Analyses revealed that participants reacted to thin and average size models and self with similar levels of body image satisfaction, valence, and arousal, even though thin models were perceived as highly more attractive. Positive affect images were rated higher on valence and arousal among all the picture types. With regards to the psychophysiological data, there were differences in startle reactivity among the three model-to-self comparison images, with images of Thin-to-Self Comparison eliciting more of an inhibited startle response and Thin-to-Average Comparison images eliciting more of a potentiated startle response. In terms of arousal, positive affect images were perceived as more arousing among all the picture types. Contrary to what was expected, there were no significant differences in skin conductance responsiveness between the three model-to self comparison images. The results are discussed from a social-comparison perspective with regard to affective reactivity to body image. Future research directions are proposed.

Tamez, Jeannine

2010-12-01T23:59:59.000Z

407

Calculating kinetics parameters and reactivity changes with continuous-energy Monte Carlo  

SciTech Connect

The iterated fission probability interpretation of the adjoint flux forms the basis for a method to perform adjoint weighting of tally scores in continuous-energy Monte Carlo k-eigenvalue calculations. Applying this approach, adjoint-weighted tallies are developed for two applications: calculating point reactor kinetics parameters and estimating changes in reactivity from perturbations. Calculations are performed in the widely-used production code, MCNP, and the results of both applications are compared with discrete ordinates calculations, experimental measurements, and other Monte Carlo calculations.

Kiedrowski, Brian C [Los Alamos National Laboratory; Brown, Forrest B [Los Alamos National Laboratory; Wilson, Paul [UNIV. WISCONSIN

2009-01-01T23:59:59.000Z

408

Reactive Flow Modeling of Liquid Explosives via ALE3D/Cheetah Simulations  

SciTech Connect

We carried out reactive flow simulations of liquid explosives such as nitromethane using the hydrodynamic code ALE3D coupled with equations of state and reaction kinetics modeled by the thermochemical code Cheetah. The simulation set-up was chosen to mimic cylinder experiments. For pure unconfined nitromethane we find that the failure diameter and detonation velocity dependence on charge diameter are in agreement with available experimental results. Such simulations are likely to be useful for determining detonability and failure behavior for a wide range of experimental conditions and explosive compounds.

Kuo, I W; Bastea, S; Fried, L E

2010-03-10T23:59:59.000Z

409

The central void reactivity in the Oak Ridge enriched uranium (93.2) metal sphere  

SciTech Connect

The central reactivity void worth was measured in the Oak Ridge unmoderated and unreflected uranium (93.20 wt% {sup 235}U) metal sphere by replacement measurements in a small (0.460-cm-diam) central spherical region in an 8.7427-cm-radius sphere. The central void worth was 9.165 {+-} 0.023 cents using the delayed neutron relative abundances and decay constants of Keepin, Wimett, and Zeigler to obtain the reactivity in cents from the stable reactor period measurements using the Inhour equation. This value is slightly larger than measurements with GODIVA 1 with larger cylindrical samples of uranium (93.70 wt% {sup 235}U) in the center: 135.50 {+-} 0.12 cents/mole for GODIVA 1 and 138.05 {+-} 0.34 cents/mole for the Oak Ridge sphere measurements, and the difference could be due to sample size effect. The central worth in {Delta}k units was calculated by neutron transport theory methods to be 6.02 {+-} 0.01 x 10{sup {minus}4} {Delta}k. The measured and calculated values are related by the effective delayed neutron fraction. The value of the effective delayed neutron fraction obtained in this way from the Oak Ridge sphere is 0.00657 {+-} 0.00002, which is in excellent agreement with that obtained from GODIVA 1 measurements, where the effective delayed neutron fraction was determined as the increment between delayed and prompt criticality and was 0.0066. From these Oak Ridge measurements, using the delayed neutron parameters of ENDF-B/VI to obtain the reactivity from the stable reactor period measurements, the central void worth is 7.984 {+-} 0.021 cents, and the inferred effective delayed neutron fraction is 0.00754. This central void worth and effective delayed neutron fractions are 14.2% higher than those obtained from use of the Keepin et al. delayed neutron data and produce a value of delayed neutron fraction in disagreement with GODIVA 1 measurements, thus questioning the usefulness of the relative abundances and decay constants of the six-group delayed neutron parameters of ENDF-B/VI for uranium for obtaining the reactivity from the measured reactor period using the Inhour equation.

Milhalczo, J.T.; Lynn, J.J.; Taylor, J.R.

1997-03-01T23:59:59.000Z

410

Drop Dynamics and Speciation in Isolation of Metals from Liquid Wastes by Reactive Scavenging  

SciTech Connect

Computational and experimental studies of the motion and dynamics of liquid drops in gas flows were conducted with relevance to reactive scavenging of metals from atomized liquid waste. Navier-Stoke's computations of deformable drops revealed a range of conditions from which prolate drops are expected, and showed how frajectiones of deformable drops undergoing deceleration can be computed. Experimental work focused on development of emission fluorescence, and scattering diagnostics. The instrument developed was used to image drop shapes, soot, and nonaxisymmetric departures from steady flow in a 22kw combustor

Arne J. Pearlstein; Alexander Scheeline

2002-08-30T23:59:59.000Z

411

Reactivation of sub-bandgap absorption in chalcogen-hyperdoped silicon  

Science Conference Proceedings (OSTI)

Silicon doped with nonequilibrium concentrations of chalcogens using a femtosecond laser exhibits near-unity absorption of sub-bandgap photons to wavelengths of at least 2500 nm. Previous studies have shown that sub-bandgap absorptance decreases with thermal annealing up to 1175 K and that the absorption deactivation correlates with chalcogen diffusivity. In this work, we show that sub-bandgap absorptance can be reactivated by annealing at temperatures between 1350 and 1550 K followed by fast cooling (>50 K/s). Our results suggest that the defects responsible for sub-bandgap absorptance are in equilibrium at high temperatures in hyperdoped Si:chalcogen systems.

Newman, Bonna K.; Buonassisi, Tonio [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Sher, Meng-Ju [Department of Physics, Harvard University, 9 Oxford Street, Cambridge, Massachusetts 02138 (United States); Mazur, Eric [Department of Physics, Harvard University, 9 Oxford Street, Cambridge, Massachusetts 02138 (United States); School of Engineering and Applied Sciences, Harvard University, 9 Oxford Street, Cambridge, Massachusetts 02138 (United States)

2011-06-20T23:59:59.000Z

412

The Dependency of Reactivity of Burn-up in Fast Reactors  

SciTech Connect

In fast reactors the poisoning effects of fission products are reduced because of relative low capture cross sections at high energies. In addition, in fluid fuel reactors there is the possibiity of removing them by processing. If plutonium production is of secondary importance to power production, then higher burnup of fuel is possible and dependency of reactivity on burnup becomes a problem of interest. One-group calculations are performed as a first step in understanding the relative effects of the initial breeding ratios, enrichment, and fissin product and heavy isotope concentration.

Sehnert, R.H.

1953-07-31T23:59:59.000Z

413

Systems and methods for reactive distillation with recirculation of light components  

Science Conference Proceedings (OSTI)

Systems and methods for producing gas-to-liquids products using reactive distillation are provided. The method for producing gas-to-liquids products can include reacting a feedstock in a column having a distillation zone and a reaction zone to provide a bottoms stream and an overhead stream. A first portion of the overhead stream can be recycled to the column at the top of the reaction zone and second portion of the overhead stream can be recycled to the column at the bottom of the reaction zone.

Stickney, Michael J. (Nassau Bay, TX); Jones, Jr., Edward M. (Friendswood, TX)

2011-07-26T23:59:59.000Z

414

Hanford ferrocyanide waste chemistry and reactivity preliminary catalyst and initiator screening studies  

Science Conference Proceedings (OSTI)

During the 1950s, ferrocyanide was used to scavenge radiocesium from aqueous nitrate-containing Hanford wastes. During the production of defense materials and while these wastes were stored in high-level waste tanks at the Hanford Site, some of these wastes were likely mixed with other waste constituents and materials. Recently, Pacific Northwest Laboratory (PNL) was commissioned by Westinghouse Hanford Company (WHC) to investigate the chemical reactivity of these ferrocyanide-bearing wastes. Because of known or potential thermal reactivity hazards associated with ferrocyanide- and nitrate-bearing wastes, and because of the potential for different materials to act as catalysts or initiators of the reactions about which there is concern, we at PNL have begun investigating the effects of the other potential waste constituents. This report presents the results of a preliminary screening study to identify classes of materials that might be in the Hanford high-level waste tanks and that could accelerate or reduce the starting temperature of the reaction(s) of concern. We plan to use the resulted of this study to determine which materials or class of materials merit additional research.

Scheele, R.D.; Bryan, S.A.; Johnston, J.W.; Tingey, J.M.; Burger, L.L.; Hallen, R.T.

1992-05-01T23:59:59.000Z

415

Fe/Si(001) Ferromagnetic Layers: Reactivity, Local Atomic Structure and Magnetism  

SciTech Connect

Ultrathin ferromagnetic Fe layers on Si(001) have recently been synthesized using the molecular beam epitaxy (MBE) technique, and their structural and magnetic properties, as well as their interface reactivity have been investigated. The study was undertaken as function of the amount of Fe deposited and of substrate temperature. The interface reactivity was characterized by Auger electron spectroscopy (AES). The surface structure was characterized by low-energy electron diffraction (LEED). The magnetism was investigated by magneto-optical Kerr effect (MOKE). A higher deposition temperature stabilizes a better surface ordering, but it also enhances Fe and Si interdiffusion and it therefore decreases the magnetism. Despite the rapid disappearance of the long range order with Fe deposition at room temperature, the material exhibits a significant uniaxial in-plane magnetic anisotropy. For the Fe deposition performed at high temperature (500 deg. C), a weak ferromagnetism is still observed, with saturation magnetization of about 10% of the value obtained previously. MOKE studies allowed inferring the main properties of the distinct formed layers.

Lungu, G. A.; Costescu, R. M.; Husanu, M. A.; Gheorghe, N. G. [National Institute of Materials Physics, Atomistilor 105bis, 077125 Magurele-Ilfov (Romania)

2011-10-03T23:59:59.000Z

416

Effect of burnup on ACR-700 3-D reactivity devices cross sections  

Science Conference Proceedings (OSTI)

Full core analysis of typical power reactors being generally performed using few groups diffusion theory, it is necessary to generate beforehand, using a lattice code, the required few group cross sections and diffusion coefficients associated with each region in the core. For CANDU-type reactors including the Advanced CANDU Reactor (ACR), the problem is more complex because these reactors contain vertical reactivity devices that are located between two horizontal fuel bundles. The usual calculation scheme relies in this case on a 2-D fuel cell calculation to generate the few group fuel properties and on a 3-D supercell calculation for the analysis of the reactivity devices present in the core. Because of its complexity, the supercell calculations are generally performed using simplified fuel geometries. In this paper, the different stages involved in the reactor physics simulations for ACR will be explained focusing particularly on a study of the burnup dependence of the incremental cross section associated with zone control units (ZCU). The use of these incremental cross sections for finite core calculations will also be presented. (authors)

Dahmani, M.; Marleau, G.; Varin, E. [Institut de Genie Nucleaire, Ecole Polytechnique de Montreal, 2900 Boulevard Edouard-Montpetit, Montreal, Que. H3T 1J4 (Canada)

2006-07-01T23:59:59.000Z

417

Evaluation of the coolant reactivity coefficient influence on the dynamic response of a small LFR system  

Science Conference Proceedings (OSTI)

An assessment of the coolant reactivity feedback influence on a small Lead-cooled Fast Reactor (LFR) dynamics has been made aimed at providing both qualitative and quantitative insights into the system transient behavior depending on the sign of the above mentioned coefficient. The need of such an investigation has been recognized since fast reactors cooled by heavy liquid metals show to be characterized by a strong coupling between primary and secondary systems. In particular, the coolant density and radial expansion coefficients have been attested to play a major role in determining the core response to any perturbed condition on the Steam Generator (SG) side. The European Lead-cooled System (ELSY)-based demonstrator (DEMO) has been assumed as the reference LFR case study. As a first step, a zero-dimensional dynamics model has been developed and implemented in MATLAB/SIMULINK{sup R} environment; then typical transient scenarios have been simulated by incorporating the actual negative lead density reactivity coefficient and its opposite. In all the examined cases results have shown that the reactor behaves in a completely different way when considering a positive coolant feedback instead of the reference one, the system free dynamics resulting moreover considerably slower due to the core and SG mutually conflicting reactions. The outcomes of the present analysis may represent a useful feedback for both the core and the control system designers. (authors)

Lorenzi, S.; Bortot, S.; Cammi, A.; Ponciroli, R. [Dept. of Energy, Nuclear Engineering Div. - CeSNEF, Politecnico di Milano, Via La Masa 34, 20156 Milano (Italy)

2012-07-01T23:59:59.000Z

418

Development of reactivity feedback effect measurement techniques under sub-critical condition in fast reactors  

Science Conference Proceedings (OSTI)

The first-of-a-kind reactor has been licensed by a safety examination of the plant design based on the measured data in precedent mock-up experiments. The validity of the safety design can be confirmed without a mock-up experiment, if the reactor feed-back characteristics can be measured before operation, with the constructed reactor itself. The 'Synthesis Method', a systematic and sophisticated method of sub-criticality measurement, is proposed in this work to ensure the safety margin before operation. The 'Synthesis Method' is based on the modified source multiplication method (MSM) combined with the noise analysis method to measure the reference sub-criticality level for MSM. A numerical simulation for the control-rod reactivity worth and the isothermal feed-back reactivity was conducted for typical fast reactors of 100 MWe-size, 300 MWe-size, 750 MWe-size, and 1500 MWe-size to investigate the applicability of Synthesis Method. The number of neutron detectors and their positions necessary for the measurement were investigated for both methods of MSM and the noise analysis by a series of parametric survey calculations. As a result, it was suggested that a neutron detector located above the core center and three or more neutron detectors located above the radial blanket region enable the measurement of sub-criticality within 10% uncertainty from -$0.5 to -$2 and within 15% uncertainty for the deeper sub-criticality. (authors)

Kitano, A.; Nishi, H. [Japan Atomic Energy Agency, 1 1, Shiraki, Tsuruga-shi, Fukui-ken, 919-1279 (Japan); Suzuki, T. [Japan Atomic Energy Agency, 2-4, Shirakata-Shirane, Tokai-mura, Naka-gun, Ibaraki-ken, 319-1195 (Japan); Okajima, S.; Kanemoto, S. [Univ. of Aizu, Tsuruga, Ikki-machi, Aizu-Wakamatsu-shi, Fukushima-ken, 965-8580 (Japan)

2012-07-01T23:59:59.000Z

419

Journey to Flexible, Reliable, Laboratory Platform for Simultaneous Control of Multiple Reactive Power Producing Devices  

SciTech Connect

Herein is discussed the instrumentation and control requirements for achieving the goal of operating multiple Distributed Energy (DE) devices in parallel to regulate local voltage. The process for establishing the flexible laboratory control and data acquisition system that allows for the integration of multiple Distributed Energy (DE) devices in XXXX Laboratory's Distributed Energy - Communications and Controls Laboratory (DECC) is discussed. The DE devices control local distribution system voltage through dynamic reactive power production. Although original efforts were made to control the reactive power (RP) output using information from commercially available meters specifically designed for monitoring and analyzing electric power values, these "intelligent" meters did not provide the flexibility needed. A very flexible and capable real-time monitoring and control system was selected after the evaluation of various methods of data acquisition (DAQ) and control. The purpose of this paper is to describe the DAQ and controls system development. The chosen controller is a commercially available real-time controller from dSPACE. This controller has many excellent features including a very easy programming platform through Simulink and Matlab's Real Time Workshop. The dSPACE system proved to provide both the flexibility and expandability needed to integrate and control the RP producing devices under consideration. The desire was to develop controls with this flexible laboratory instrumentation and controls setup that could be eventually be included in an embedded controller on a DE device. Some experimental results are included that clearly show that some functional control strategies are currently being tested.

Foster, Jason [ORNL; Rizy, D Tom [ORNL; Kueck, John D [ORNL

2007-01-01T23:59:59.000Z

420

Absolute reactivity calibration of accelerator-driven systems after RACE-T experiments  

Science Conference Proceedings (OSTI)

The RACE-T experiments that were held in november 2005 in the ENEA-Casaccia research center near Rome allowed us to improve our knowledge of the experimental techniques for absolute reactivity calibration at either startup or shutdown phases of accelerator-driven systems. Various experimental techniques for assessing a subcritical level were inter-compared through three different subcritical configurations SC0, SC2 and SC3, about -0.5, -3 and -6 dollars, respectively. The area-ratio method based of the use of a pulsed neutron source appears as the most performing. When the reactivity estimate is expressed in dollar unit, the uncertainties obtained with the area-ratio method were less than 1% for any subcritical configuration. The sensitivity to measurement location was about slightly more than 1% and always less than 4%. Finally, it is noteworthy that the source jerk technique using a transient caused by the pulsed neutron source shutdown provides results in good agreement with those obtained from the area-ratio technique. (authors)

Jammes, C. C. [Commissariat a l'Energie Atomique CEA, Centre de Cadarache, DEN/CAD/DER/SPEx/LPE, 13108 Saint Paul-Lez-Durance (France); Imel, G. R. [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439 (United States); Geslot, B. [Commissariat a l'Energie Atomique CEA, Centre de Cadarache, DEN/CAD/DER/SPEx/LPE, 13108 Saint Paul-Lez-Durance (France); Rosa, R. [Ente per le Nuove Tecnologie, L'Energia e l'Ambiente, Centro della Casaccia, Via Anguillarese, 301, 00060 Roma I (Italy)

2006-07-01T23:59:59.000Z

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421

Variably Saturated Flow and Multicomponent Biogeochemical Reactive Transport Modeling of a Uranium Bioremediation Field Experiment  

Science Conference Proceedings (OSTI)

Field experiments at a former uranium mill tailings site have identified the potential for stimulating indigenous bacteria to catalyze the conversion of aqueous uranium in the +6 oxidation state to immobile solid-associated uranium in the +4 oxidation state. This effectively removes uranium from solution resulting in groundwater concentrations below actionable standards. Three-dimensional, coupled variably-saturated flow and biogeochemical reactive transport modeling of a 2008 in situ uranium bioremediation field experiment is used to better understand the interplay of transport rates and biogeochemical reaction rates that determine the location and magnitude of key reaction products. A comprehensive reaction network, developed largely through previous 1-D modeling studies, was used to simulate the impacts on uranium behavior of pulsed acetate amendment, seasonal water table variation, spatially-variable physical (hydraulic conductivity, porosity) and geochemical (reactive surface area) material properties. A principal challenge is the mechanistic representation of biologically-mediated terminal electron acceptor process (TEAP) reactions whose products significantly alter geochemical controls on uranium mobility through increases in pH, alkalinity, exchangeable cations, and highly reactive reduction products. In general, these simulations of the 2008 Big Rusty acetate biostimulation field experiment in Rifle, Colorado confirmed previously identified behaviors including (1) initial dominance by iron reducing bacteria that concomitantly reduce aqueous U(VI), (2) sulfate reducing bacteria that become dominant after {approx}30 days and outcompete iron reducers for the acetate electron donor, (3) continuing iron-reducer activity and U(VI) bioreduction during dominantly sulfate reducing conditions, and (4) lower apparent U(VI) removal from groundwater during dominantly sulfate reducing conditions. New knowledge on simultaneously active metal and sulfate reducers has been incorporated into the modeling. In this case, an initially small population of slow growing sulfate reducers is active from the initiation of biostimulation. Three-dimensional, variably saturated flow modeling was used to address impacts of a falling water table during acetate injection. These impacts included a significant reduction in aquifer saturated thickness and isolation of residual reactants and products, as well as unmitigated uranium, in the newly unsaturated vadose zone. High permeability sandy gravel structures resulted in locally high flow rates in the vicinity of injection wells that increased acetate dilution. In downgradient locations, these structures created preferential flow paths for acetate delivery that enhanced local zones of TEAP reactivity and subsidiary reactions. Conversely, smaller transport rates associated with the lower permeability lithofacies (e.g., fine) and vadose zone were shown to limit acetate access and reaction. Once accessed by acetate, however, these same zones limited subsequent acetate dilution and provided longer residence times that resulted in higher concentrations of TEAP products when terminal electron donors and acceptors were not limiting. Finally, facies-based porosity and reactive surface area variations were shown to affect aqueous uranium concentration distributions; however, the ranges were sufficiently small to preserve general trends. Large computer memory and high computational performance were required to simulate the detailed coupled process models for multiple biogeochemical components in highly resolved heterogeneous materials for the 110-day field experiment and 50 days of post-biostimulation behavior. In this case, a highly-scalable subsurface simulator operating on 128 processor cores for 12 hours was used to simulate each realization. An equivalent simulation without parallel processing would have taken 60 days, assuming sufficient memory was available.

Yabusaki, Steven B.; Fang, Yilin; Williams, Kenneth H.; Murray, Christopher J.; Ward, Anderson L.; Dayvault, Richard; Waichler, Scott R.; Newcomer, Darrell R.; Spane, Frank A.; Long, Philip E.

2011-11-01T23:59:59.000Z

422

A reaction-based paradigm to model reactive chemical transport in groundwater with general kinetic and equilibrium reactions  

Science Conference Proceedings (OSTI)

This paper presents a reaction-based water quality transport model in subsurface flow systems. Transport of chemical species with a variety of chemical and physical processes is mathematically described by M partial differential equations (PDEs). Decomposition via Gauss-Jordan column reduction of the reaction network transforms M species reactive transport equations into two sets of equations: a set of thermodynamic equilibrium equations representing NE equilibrium reactions and a set of reactive transport equations of M-NE kinetic-variables involving no equilibrium reactions (a kinetic-variable is a linear combination of species). The elimination of equilibrium reactions from reactive transport equations allows robust and efficient numerical integration. The model solves the PDEs of kinetic-variables rather than individual chemical species, which reduces the number of reactive transport equations and simplifies the reaction terms in the equations. A variety of numerical methods are investigated for solving the coupled transport and reaction equations. Simulation comparisons with exact solutions were performed to verify numerical accuracy and assess the effectiveness of various numerical strategies to deal with different application circumstances. Two validation examples involving simulations of uranium transport in soil columns are presented to evaluate the ability of the model to simulate reactive transport with complex reaction networks involving both kinetic and equilibrium reactions.

Zhang, Fan [ORNL; Yeh, Gour-Tsyh [University of Central Florida, Orlando; Parker, Jack C [ORNL; Brooks, Scott C [ORNL; Pace, Molly [ORNL; Kim, Young Jin [ORNL; Jardine, Philip M [ORNL; Watson, David B [ORNL

2007-01-01T23:59:59.000Z

423

Reaction mechanism of cumene hydroperoxide decomposition in cumene and evaluation of its reactivity hazards  

E-Print Network (OSTI)

Cumene hydroperoxide (CHP), a type of organic peroxide, is widely used in the chemical industry for diverse applications. However, it decomposes and undergoes highly exothermic runaway reactions under high temperature because of its unstable peroxide functional group. The risk of runaway reaction is intensified by the fact that operation temperature of CHP is close to its onset temperature in many cases. To ensure safe handling of CHP in the chemical industry, a lot of research has been done on it including theoretical research at the microscopic level and experimental research at the macroscopic level. However, the unstable radicals in the CHP decomposition reactions make it difficult to study its reaction pathway, and therefore lead to incomplete understanding of the reaction mechanism. The slow progress in theoretical research hinders the application of the theoretical prediction in experimental research. For experimental research, the lack of integration of operational parameters into the reactivity evaluation limits its application in industrial process. In this thesis, a systematic methodology is proposed to evaluate the reactivity hazards of CHP. This methodology is a combination of theoretical research using computational quantum chemistry method and experimental research using RSSTTM. The theoretical research determined the dominant reaction pathway of CHP decomposition reaction through the study of thermodynamic and kinetic stability, which was applied to the analysis of experimental results. The experimental research investigated the effect of CHP concentration on runaway reactions by analyzing the important parameters including temperature, pressure, self-heat rate and pressure rate. This methodology could also be applied to other organic peroxides or other reactive chemicals. The results of theoretical research on reaction mechanism show that there is a dominant reaction pathway, which consumes most of the CHP in decomposition reaction. This conclusion agrees with the experimental results that 40 wt% is a critical point for almost all important parameters of runaway reactions. In the high concentration range above 40 wt%, some unknown reaction pathways are involved in decomposition of CHP because of lack of cumene. The shift of reaction mechanism causes the change of the effect of concentration on runaway reactions.

Lu, Yuan

2008-08-01T23:59:59.000Z

424

Geophysical monitoring and reactive transport modeling of ureolytically-driven calcium carbonate precipitation  

SciTech Connect

Ureolytically-driven calcium carbonate precipitation is the basis for a promising in-situ remediation method for sequestration of divalent radionuclide and trace metal ions. It has also been proposed for use in geotechnical engineering for soil strengthening applications. Monitoring the occurrence, spatial distribution, and temporal evolution of calcium carbonate precipitation in the subsurface is critical for evaluating the performance of this technology and for developing the predictive models needed for engineering application. In this study, we conducted laboratory column experiments using natural sediment and groundwater to evaluate the utility of geophysical (complex resistivity and seismic) sensing methods, dynamic synchrotron x-ray computed tomography (micro-CT), and reactive transport modeling for tracking ureolytically-driven calcium carbonate precipitation processes under site relevant conditions. Reactive transport modeling with TOUGHREACT successfully simulated the changes of the major chemical components during urea hydrolysis. Even at the relatively low level of urea hydrolysis observed in the experiments, the simulations predicted an enhanced calcium carbonate precipitation rate that was 3-4 times greater than the baseline level. Reactive transport modeling results, geophysical monitoring data and micro-CT imaging correlated well with reaction processes validated by geochemical data. In particular, increases in ionic strength of the pore fluid during urea hydrolysis predicted by geochemical modeling were successfully captured by electrical conductivity measurements and confirmed by geochemical data. The low level of urea hydrolysis and calcium carbonate precipitation suggested by the model and geochemical data was corroborated by minor changes in seismic P-wave velocity measurements and micro-CT imaging; the latter provided direct evidence of sparsely distributed calcium carbonate precipitation. Ion exchange processes promoted through NH{sub 4}{sup +} production during urea hydrolysis were incorporated in the model and captured critical changes in the major metal species. The electrical phase increases were potentially due to ion exchange processes that modified charge structure at mineral/water interfaces. Our study revealed the potential of geophysical monitoring for geochemical changes during urea hydrolysis and the advantages of combining multiple approaches to understand complex biogeochemical processes in the subsurface.

Wu, Y.; Ajo-Franklin, J.B.; Spycher, N.; Hubbard, S.S.; Zhang, G.; Williams, K.H.; Taylor, J.; Fujita, Y.; Smith, R.

2011-07-15T23:59:59.000Z

425

QUANTIFICATION OF FUGITIVE REACTIVE ALKENE EMISSIONS FROM PETROCHEMICAL PLANTS WITH PERFLUOROCARBON TRACERS.  

SciTech Connect

Recent studies demonstrate the impact of fugitive emissions of reactive alkenes on the atmospheric chemistry of the Houston Texas metropolitan area (1). Petrochemical plants located in and around the Houston area emit atmospheric alkenes, such as ethene, propene and 1,3-butadiene. The magnitude of emissions is a major uncertainty in assessing their effects. Even though the petrochemical industry reports that fugitive emissions of alkenes have been reduced to less than 0.1% of daily production, recent measurement data, obtained during the TexAQS 2000 experiment indicates that emissions are perhaps a factor of ten larger than estimated values. Industry figures for fugitive emissions are based on adding up estimated emission factors for every component in the plant to give a total estimated emission from the entire facility. The dramatic difference between estimated and measured rates indicates either that calculating emission fluxes by summing estimates for individual components is seriously flawed, possibly due to individual components leaking well beyond their estimated tolerances, that not all sources of emissions for a facility are being considered in emissions estimates, or that there are known sources of emissions that are not being reported. This experiment was designed to confirm estimates of reactive alkene emissions derived from analysis of the TexAQS 2000 data by releasing perfluorocarbon tracers (PFTs) at a known flux from a petrochemical plant and sampling both the perfluorocarbon tracer and reactive alkenes downwind using the Piper-Aztec research aircraft operated by Baylor University. PFTs have been extensively used to determine leaks in pipelines, air infiltration in buildings, and to characterize the transport and dispersion of air parcels in the atmosphere. Over 20 years of development by the Tracer Technology Center (TTC) has produced a range of analysis instruments, field samplers and PFT release equipment that have been successfully deployed in a large variety of experiments. PFTs are inert, nontoxic, noncombustible and nonreactive. Up to seven unique PFTs can be simultaneously released, sampled and analyzed and the technology is well suited for determining emission fluxes from large petrochemical facilities. The PFT experiment described here was designed to quantitate alkene emissions from a single petrochemical facility, but such experiments could be applied to other industrial sources or groups of sources in the Houston area.

SENUM,G.I.; DIETZ,R.N.

2004-06-30T23:59:59.000Z

426

Geophysical Monitoring and Reactive Transport Modeling of Ureolytically-Driven Calcium Carbonate Precipitation  

Science Conference Proceedings (OSTI)

Ureolytically-driven calcium carbonate precipitation is the basis for a promising in-situ remediation method for sequestration of divalent radionuclide and trace metal ions. It has also been proposed for use in geotechnical engineering for soil strengthening applications. Monitoring the occurrence, spatial distribution, and temporal evolution of calcium carbonate precipitation in the subsurface is critical for evaluating the performance of this technology and for developing the predictive models needed for engineering application. In this study, we conducted laboratory column experiments using natural sediment and groundwater to evaluate the utility of geophysical (complex resistivity and seismic) sensing methods, dynamic synchrotron x-ray computed tomography (micro-CT), and reactive transport modeling for tracking ureolytically-driven calcium carbonate precipitation processes under site relevant conditions. Reactive transport modeling with TOUGHREACT successfully simulated the changes of the major chemical components during urea hydrolysis. Even at the relatively low level of urea hydrolysis observed in the experiments, the simulations predicted an enhanced calcium carbonate precipitation rate that was 3-4 times greater than the baseline level. Reactive transport modeling results, geophysical monitoring data and micro-CT imaging correlated well with reaction processes validated by geochemical data. In particular, increases in ionic strength of the pore fluid during urea hydrolysis predicted by geochemical modeling were successfully captured by electrical conductivity measurements and confirmed by geochemical data. The low level of urea hydrolysis and calcium carbonate precipitation suggested by the model and geochemical data was corroborated by minor changes in seismic P-wave velocity measurements and micro-CT imaging; the latter provided direct evidence of sparsely distributed calcium carbonate precipitation. Ion exchange processes promoted through NH4+ production during urea hydrolysis were incorporated in the model and captured critical changes in the major metal species. The electrical phase increases were potentially due to ion exchange processes that modified charge structure at mineral/water interfaces. Our study revealed the potential of geophysical monitoring for geochemical changes during urea hydrolysis and the advantages of combining multiple approaches to understand complex biogeochemical processes in the subsurface.

Yuxin Wu; Jonathan B. Ajo-Franklin; Nicolas Spycher; Susan S. Hubbard; Guoxiang Zhang; Kenneth H. Williams; Joanna Taylor; Yoshiko Fujita; Robert Smith

2011-09-01T23:59:59.000Z

427

TOUGHREACT: a new code of the TOUGH Family for Non-Isothermal multiphase reactive geochemical transport in variably saturated geologic media  

E-Print Network (OSTI)

multiphase flow, solute transport and reactive chemistry in porousmultiphase fluid flow, mass transport and chemical reactions, (2) we consider not only porous

Xu, Tianfu; Sonnenthal, Eric; Spycher, Nicolas; Pruess, Karsten

2003-01-01T23:59:59.000Z

428

Improved generation of large-scale atomistic representations and pyrolysis/combustion simulations of Illinois coal and coal char using the Reaxff reactive force field.  

E-Print Network (OSTI)

??A highly automated molecular generation approach was implemented and coupled with reactive force field methods to create a new computational capability that enabled the investigation… (more)

Castro Marcano, Fidel

2012-01-01T23:59:59.000Z

429

Investigating the potential for long-term permeable reactive barrier (PRB) monitoring from the electrical signatures associated with the reduction in reactive iron performance  

SciTech Connect

The objective of this work was to conduct laboratory and field experiments to determine the sensitivity of low frequency electrical measurements (resistivity and induced polarization) to the processes of corrosion and precipitation that are believed to limit permeable reactive barrier (PRB) performance. The research was divided into four sets of experiments that were each written up and submitted to a peer-reviewed journal: [1] A laboratory experiment to define the controls of aqueous chemistry (electrolyte activity; pH; valence) and total zero valent iron (Fe0) available surface area on the electrical properties of Fe0 columns. [2] A laboratory experiment to determine the impact of corrosion and precipitation on the electrical response of synthetic Fe0 columns as a result of geochemical reactions with NaSO4 and NaCO3 electrolytes. [3] Laboratory experiments on a sequence of cores retrieved from the Kansas City PRB to determine the magnitude of electrical and geochemical changes within a field active PRB after eight years of operation [4] Field-scale cross borehole resistivity and induced polarization monitoring of the Kansas City PRB to evaluate the potential of electrical imaging as a technology for non-invasive, long-term monitoring of indicators of reduced PRB performance This report first summarizes the findings of the four major experiments conducted under this research. The reader is referred to the four papers in Appendices 1-4 for a full description of each experiment, including motivation and significance, technical details, findings and implications. The deliverables of the project, including the publications, conference papers and new collaborative arrangements that have resulted are then described. Appendices 5-6 contain two technical reports written by co-PI Korte describing (1) supporting geochemical measurements, and (2) the coring procedure, conducted at the Kansas City PRB as part of this project.

Slater, Lee D.; Korte, N.; Baker, J.

2005-12-14T23:59:59.000Z

430

Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Volume 1, Bench-scale testing and analysis  

Science Conference Proceedings (OSTI)

AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

Jha, M.C.; Berggren, M.H.

1989-05-02T23:59:59.000Z

431

Chombo-Crunch: Modeling Pore-Scale Reactive Transport in Carbon  

NLE Websites -- All DOE Office Websites (Extended Search)

Transient pH on calcite grains in capillary tube experiment. 1 billion grid points computed on 48K cores. 1 micron resolution. Transient pH on calcite grains in capillary tube experiment. 1 billion grid points computed on 48K cores. 1 micron resolution. Transient pH on calcite grains in capillary tube experiment. 1 billion grid points computed on 48K cores. 1 micron resolution. David Trebotich, Lawrence Berkeley National Laboratory Chombo-Crunch: Modeling Pore-Scale Reactive Transport in Carbon Sequestration PI Name: David Trebotich PI Email: treb@lbl.gov Institution: Lawrence Berkeley National Laboratory Allocation Program: INCITE Allocation Hours at ALCF: 80 Million Year: 2014 Research Domain: Earth Science Carbon sequestration, the process of capturing carbon dioxide (CO2) before it enters the atmosphere and transferring it into the earth, is a promising technique to help control greenhouse gas emissions. Researchers from the

432

Feasibility of direct reactivity measurement in multi-canister overpacks at the Cold Vacuum Drying Facility  

DOE Green Energy (OSTI)

A proposed method for measuring the chemical reaction rate (power) of breached N-Reactor fuel elements with water in a Multi-canister overpack (MCO) based on hydrogen release rate is evaluated. The reaction rate is measured at 50 C in an oxygen free water by applying a vacuum to boil the water and adding a low, measured flow of helium. The ratio of helium to hydrogen is used to infer the reaction rate. A test duration of less than 8 hours was found to provide sufficient accuracy for confidence in the measurement results. A more rigorous treatment of system measurement accuracy, which may yield shorter test durations, should be performed if this reactivity measurement is to be employed.

Cowan, R.G.

1997-10-02T23:59:59.000Z

433

Formation of metal nanoparticles by short-distance sputter deposition in a reactive ion etching chamber  

Science Conference Proceedings (OSTI)

A new method is reported to form metal nanoparticles by sputter deposition inside a reactive ion etching chamber with a very short target-substrate distance. The distribution and morphology of nanoparticles are found to be affected by the distance, the ion concentration, and the sputtering time. Densely distributed nanoparticles of various compositions were fabricated on the substrates that were kept at a distance of 130 mum or smaller from the target. When the distance was increased to 510 mum, island structures were formed, indicating the tendency to form continuous thin film with longer distance. The observed trend for nanoparticle formation is opposite to the previously reported mechanism for the formation of nanoparticles by sputtering. A new mechanism based on the seeding effect of the substrate is proposed to interpret the experimental results.

Nie Min; Meng, Dennis Desheng [Department of Mechanical Engineering and Engineering Mechanics, Michigan Technological University, Houghton, Michigan 49931 (United States); Sun Kai [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2009-09-01T23:59:59.000Z

434

Method for cracking hydrocarbon compositions using a submerged reactive plasma system  

DOE Patents (OSTI)

A method for cracking a liquid hydrocarbon composition (e.g. crude oil) to produce a cracked hydrocarbon product. A liquid hydrocarbon composition is initially provided. An electrical arc is generated directly within the hydrocarbon composition so that the arc is entirely submerged in the composition. Arc generation is preferably accomplished using a primary and secondary electrode each having a first end submerged in the composition. The first ends of the electrodes are separated from each other to form a gap therebetween. An electrical potential is then applied to the electrodes to generate the arc within the gap. A reactive gas is thereafter delivered to the arc which forms a bubble around the arc. Gas delivery may be accomplished by providing a passageway through each electrode and delivering the gas through the passageways. The arc and gas cooperate to produce a plasma which efficiently cracks the hydrocarbon composition.

Kong, Peter C. (Idaho Falls, ID)

1997-01-01T23:59:59.000Z

435

Method for cracking hydrocarbon compositions using a submerged reactive plasma system  

DOE Patents (OSTI)

A method is described for cracking a liquid hydrocarbon composition (e.g. crude oil) to produce a cracked hydrocarbon product. A liquid hydrocarbon composition is initially provided. An electrical arc is generated directly within the hydrocarbon composition so that the arc is entirely submerged in the composition. Arc generation is preferably accomplished using a primary and secondary electrode each having a first end submerged in the composition. The first ends of the electrodes are separated from each other to form a gap there between. An electrical potential is then applied to the electrodes to generate the arc within the gap. A reactive gas is thereafter delivered to the arc which forms a bubble around the arc. Gas delivery may be accomplished by providing a passageway through each electrode and delivering the gas through the passageways. The arc and gas cooperate to produce a plasma which efficiently cracks the hydrocarbon composition. 6 figs.

Kong, P.C.

1997-05-06T23:59:59.000Z

436

Characterization of the reactive flow field dynamics in a gas turbine injector using high frequency PIV  

E-Print Network (OSTI)

The present work details the analysis of the aerodynamics of an experimental swirl stabilized burner representative of gas turbine combustors. This analysis is carried out using High Frequency PIV (HFPIV) measurements in a reactive situation. While this information is usually available at a rather low rate, temporally resolved PIV measurements are necessary to better understand highly turbulent swirled flows, which are unsteady by nature. Thanks to recent technical improvements, a PIV system working at 12 kHz has been developed to study this experimental combustor flow field. Statistical quantities of the burner are first obtained and analyzed, and the measurement quality is checked, then a temporal analysis of the velocity field is carried out, indicating that large coherent structures periodically appear in the combustion chamber. The frequency of these structures is very close to the quarter wave mode of the chamber, giving a possible explanation for combustion instability coupling.

Barbosa, Séverine; Ducruix, Sébastien

2008-01-01T23:59:59.000Z

437

Energy dependence of ion-assisted chemical etch rates in reactive plasmas  

Science Conference Proceedings (OSTI)

In a highly cited paper, Steinbruechel [C. Steinbruechel, Appl. Phys. Lett. 55, 1960 (1989)] has demonstrated that in the sub-keV region the etch yield scales like the square root of the ion energy. Based on this result, many authors have subsequently applied this specific energy dependence to ion-assisted chemical etch rates of various materials in different etch tools. In this work, it is demonstrated that in contrast to the etch yield, the etch rate cannot universally be modeled by a simple square-root energy dependence. A novel model accounting for the correct energy dependence of ion-assisted chemical etch rates is therefore proposed. Application of this model to the etching of SiO{sub 2} and ZnO in halogenated plasma chemistries provides a quantitative description of the simultaneous dependence of the etch rate on ion energy and on ion and reactive neutral fluxes.

Stafford, L.; Margot, J.; Chaker, M.; Pearton, S.J. [Departement de physique, Universite de Montreal, Montreal, Quebec (Canada); INRS-Energie, Materiaux et Telecommunications, Varennes, Quebec (Canada); Department of Materials Science and Engineering, University of Florida, Gainesville, Florida (United States)

2005-08-15T23:59:59.000Z

438

Reactivity feedback from irradiated pin failure in unprotected slow TOP accidents in LMFBR's  

SciTech Connect

The present work is an outgrowth of studies made in support of CRBR licensing, but the conclusions drawn should be generally applicable to oxide-fueled LMFBR's. The accident under consideration is a 10 cents/s unprotected TOP (transient overpower), for which a series of PLUTO2/SAS4A calculations has been performed using a higher power CRBR EOC3 fuel pin which had 275 days irradiation. The assumption was made in the licensing work that a short pin failure will occur at the axial midplane, maximizing the positive fuel motion reactivity effect, as it was felt that a less conservative assumption could not be conclusively justified. This assumption is also made in the present case.

Hummel, H.H.; Pizzica, P.A.

1984-09-19T23:59:59.000Z

439

Nanostructures and Lithium Electrochemical Reactivity of Lithium Titanites and Titanium Oxides: A Review  

SciTech Connect

Being inherently safe and chemically compatible with the electrolyte, titanium oxidebased materials, including both Li-titanites and various TiO2-polymorphs, are considered alternatives to carbonaceous anodes in Li-ion batteries. Given the commercial success of the spinel lithium titanites, TiO2-polymorphs, in particular in nanostructured forms, have been fabricated and investigated for the applications. Nanostructuring leads to increased reaction areas, shortened Li+ diffusion and potentially enhanced solubility/capacity. Integration with an electron conductive second phase into the TiO2-based nanostructures eases the electron transport, resulting in further improved lithium electrochemical activity and the overall electrochemical performance. This paper reviews structural characteristics and Li-electrochemical reactivity, along with synthetic approaches, of nanostructures and nano-composites based on lithium titanites and TiO2-polymorphs that include rutile, anatase, bronze and brookite.

Yang, Zhenguo; Choi, Daiwon; Kerisit, Sebastien N.; Rosso, Kevin M.; Wang, Donghai; Zhang, Jiguang; Graff, Gordon L.; Liu, J.

2009-07-15T23:59:59.000Z

440

Chemically reactive coatings for passive fire protection in LNG and LPG storage and transporation  

SciTech Connect

According to Van Dyke Associates and TSI Inc., supporting and containing steels used to store and transport LNG and LPG are best protected in case of fire by thermally reactive subliming compounds. When exposed to fire, such compounds undergo an endothermic reaction; thus the substrate material beneath the coating will not heat up beyond the temperature at which this reaction occurs. Gases released by the sublimation reaction pass outward through the pores of the char, breaking down further as they absorb more energy. Numerous tests confirm that in comparison with other types of coatings, subliming compounds require the smallest thickness of coating for any specified level of protection. Routine spraying application techniques further reduce the cost of this passive fire-protection method.

Van Dyke, B.H.; Kawaller, S.T.

1979-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "volt ampere reactive" from the National Library of EnergyBeta (NLEBeta).
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441

Boron-carbide-aluminum and boron-carbide-reactive metal cermets  

SciTech Connect

Hard, tough, lightweight boron-carbide-reactive metal composites, particularly boron-carbide-aluminum composites, are produced. These composites have compositions with a plurality of phases. A method is provided, including the steps of wetting and reacting the starting materials, by which the microstructures in the resulting composites can be controllably selected. Starting compositions, reaction temperatures, reaction times, and reaction atmospheres are parameters for controlling the process and resulting compositions. The ceramic phases are homogeneously distributed in the metal phases and adhesive forces at ceramic-metal interfaces are maximized. An initial consolidation step is used to achieve fully dense composites. Microstructures of boron-carbide-aluminum cermets have been produced with modulus of rupture exceeding 110 ksi and fracture toughness exceeding 12 ksi.sqroot.in. These composites and methods can be used to form a variety of structural elements.

Halverson, Danny C. (Manteca, CA); Pyzik, Aleksander J. (Seattle, WA); Aksay, Ilhan A. (Seattle, WA)

1986-01-01T23:59:59.000Z

442

Development and feasibility of a waste package coupled reactive transport model (AREST-CT)  

Science Conference Proceedings (OSTI)

Most models that analyze the waste package and engineered barrier system (near-field) of an underground geologic repository assume constant boundary conditions at the waste form surface and constant chemical properties of the groundwater. These models are useful for preliminary modeling, iterative modeling to estimate uncertainties, and as a source for a total systems analysis. However, the chemical behavior of the system is a very important factor in the containment and release of radionuclides, and one needs to understand the underlying processes involved. Therefore, the authors are developing a model to couple the calculation of the chemical properties with the reactive transport which can be used to assess the near-field. This report describes the models being implemented and presents some simple analyses demonstrating the feasibility of the chemical and coupled transport models.

Engel, D.W.; McGrail, B.P.; Fort, J.A.; Roberts, J.S.

1994-05-01T23:59:59.000Z

443

Reactive and voltage monitoring: The challenge for the system operators in the 1980's  

Science Conference Proceedings (OSTI)

In order to gain perspective on the monitoring program for PJM, background relative to the physical characteristics and operating philosophy of the pool is offered. PJM is comprised of 11 electric utilities serving approximately 48,700 square miles, encompassing about 75% of Penna, 97% of N.J., all of Del and the District of Columbia, 60% of Md, and 1% of Va. The generating capability is comprised of 532 units at 116 generating stations, and totals approximately 45,000 MW. The PJM system peak load for 1980 was 34,420 MW. PJM has 27 tie lines with its neighboring systems. Although comprised of 11 utilities, the PJM system is operated as if it were a single company. Reasons for the PJM real-time monitoring system are presented and relevant details are discussed. Topics considered include operating criteria. Reactive and Voltage Monitoring, Current Operating Restrictions off-line analysis, and future requirements are discussed.

Willson, J.D.

1981-05-01T23:59:59.000Z

444

Catalytic reactive separation system for energy-efficient production of cumene  

DOE Patents (OSTI)

The present invention relates to an atmospheric pressure, reactive separation column packed with a solid acid zeolite catalyst for producing cumene from the reaction of benzene with propylene. Use of this un-pressurized column, where simultaneous reaction and partial separation occur during cumene production, allow separation of un-reacted, excess benzene from other products as they form. This high-yielding, energy-efficient system allows for one-step processing of cumene, with reduced need for product purification. Reacting propylene and benzene in the presence of beta zeolite catalysts generated a selectivity greater than 85% for catalytic separation reactions at a reaction temperature of 115 degrees C and at ambient pressure. Simultaneously, up to 76% of un-reacted benzene was separated from the product; which could be recycled back to the reactor for re-use.

Buelna, Genoveva (Nuevo Laredo, MX); Nenoff, Tina M. (Albuquerque, NM)

2009-07-28T23:59:59.000Z

445

Utility of reactively sputtered CuN{sub x} films in spintronics devices  

SciTech Connect

We have studied nitrified copper (CuN{sub x}) thin films grown by reactive sputtering in the context of spintronic devices. The Ar-to-N{sub 2} flow ratio enables tunability of the electrical resistivity and surface roughness of the CuN{sub x} films, with the former increasing to nearly 20 times that of Cu, and the latter reduced to the atomic scale. Incorporating this into a Ta/CuN{sub x}/Ta seed stack for spin valves improves the current-in-plane (CIP) magnetoresistance; maximum magnetoresistance results with CuN{sub x} seed layer and Cu interlayer. Finally, finite element modeling results are presented that suggest the use of CuN{sub x} in nanocontact spin torque oscillators can enhance current densities by limiting the current spread through the device. This may positively impact threshold currents, power requirements, and device reliability.

Fang Yeyu [Physics Department, Goeteborg University, 412 96 Goeteborg (Sweden); Persson, J. [Physics Department, Goeteborg University, 412 96 Goeteborg (Sweden); NanOsc AB, Electrum 205, 164 40 Kista (Sweden); Zha, C. [Materials Physics Department, Royal Institute of Technology, Electrum 229, 164 40 Kista (Sweden); Willman, J.; Miller, Casey W. [Department of Physics, Center for Integrated Functional Materials, University of South Florida, 4202 East Fowler Avenue, Tampa, Florida 33620 (United States); Aakerman, Johan [Physics Department, Goeteborg University, 412 96 Goeteborg (Sweden); NanOsc AB, Electrum 205, 164 40 Kista (Sweden); Materials Physics Department, Royal Institute of Technology, Electrum 229, 164 40 Kista (Sweden)

2012-04-01T23:59:59.000Z

446

Methods for modeling impact-induced reactivity changes in small reactors.  

SciTech Connect

This paper describes techniques for determining impact deformation and the subsequent reactivity change for a space reactor impacting the ground following a potential launch accident or for large fuel bundles in a shipping container following an accident. This technique could be used to determine the margin of subcriticality for such potential accidents. Specifically, the approach couples a finite element continuum mechanics model (Pronto3D or Presto) with a neutronics code (MCNP). DAGMC, developed at the University of Wisconsin-Madison, is used to enable MCNP geometric queries to be performed using Pronto3D output. This paper summarizes what has been done historically for reactor launch analysis, describes the impact criticality analysis methodology, and presents preliminary results using representative reactor designs.

Tallman, Tyler N.; Radel, Tracy E.; Smith, Jeffrey A.; Villa, Daniel L.; Smith, Brandon M. (U. of Wisconsin, Madison, WI); Radel, Ross F.; Lipinski, Ronald J.; Wilson, Paul Philip Hood (U. of Wisconsin, Madison, WI)

2010-10-01T23:59:59.000Z

447

Hall mobility of cuprous oxide thin films deposited by reactive direct-current magnetron sputtering  

Science Conference Proceedings (OSTI)

Cuprous oxide (Cu{sub 2}O) is a promising earth-abundant semiconductor for photovoltaic applications. We report Hall mobilities of polycrystalline Cu{sub 2}O thin films deposited by reactive dc magnetron sputtering. High substrate growth temperature enhances film grain structure and Hall mobility. Temperature-dependent Hall mobilities measured on these films are comparable to monocrystalline Cu{sub 2}O at temperatures above 250 K, reaching 62 cm{sup 2}/V s at room temperature. At lower temperatures, the Hall mobility appears limited by carrier scattering from ionized centers. These observations indicate that sputtered Cu{sub 2}O films at high substrate growth temperature may be suitable for thin-film photovoltaic applications.

Lee, Yun Seog; Winkler, Mark T.; Siah, Sin Cheng; Brandt, Riley; Buonassisi, Tonio [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2011-05-09T23:59:59.000Z

448

Development of dynamic models of reactive distillation columns for simulation and determination of control  

E-Print Network (OSTI)

Dynamic models of a reactive distillation column have been developed and implemented in this work. A model describing the steady state behavior of the system has been built in a first step. The results from this steady state model have been compared to data provided from an industrial collaborator and the reconciled model formed the basis for the development of a dynamic model. Four controlled and four manipulated variables have been determined in a subsequent step and step tests for the manipulated variables were simulated. The data generated by the step responses was used for fitting transfer functions between the manipulated and the controlled variables. RGA analysis was performed to find the optimal pairing for controller design. Feedback controllers of PID type were designed between the paired variables found from RGA and the controllers were implemented on the column model. Both servo and regulatory problems have been considered and tested.

Chakrabarty, Arnab

2004-12-01T23:59:59.000Z

449

Benzene's metabolites alter c-MYB activity via reactive oxygen species in HD3 cells  

Science Conference Proceedings (OSTI)

Benzene is a known leukemogen that is metabolized to form reactive intermediates and reactive oxygen species (ROS). The c-Myb oncoprotein is a transcription factor that has a critical role in hematopoiesis. c-Myb transcript and protein have been overexpressed in a number of leukemias and cancers. Given c-Myb's role in hematopoiesis and leukemias, it is hypothesized that benzene interferes with the c-Myb signaling pathway and that this involves ROS. To investigate our hypothesis, we evaluated whether benzene, 1,4-benzoquinone, hydroquinone, phenol, and catechol generated ROS in chicken erythroblast HD3 cells, as measured by 5-(and-6)-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate (DCFDA) and dihydrorhodamine-123 (DHR-123), and whether the addition of 100 U/ml of the antioxidating enzyme superoxide dismutase (SOD) could prevent ROS generation. Reduced to oxidized glutathione ratios (GSH:GSSG) were also assessed as well as hydroquinone and benzoquinone's effects on c-Myb protein levels and activation of a transiently transfected reporter construct. Finally we attempted to abrogate benzene metabolite mediated increases in c-Myb activity with the use of SOD. We found that benzoquinone, hydroquinone, and catechol increased DCFDA fluorescence, increased DHR-123 fluorescence, decreased GSH:GSSG ratios, and increased reporter construct expression after 24 h of exposure. SOD was able to prevent DCFDA fluorescence and c-Myb activity caused by benzoquinone and hydroquinone only. These results are consistent with other studies, which suggest metabolite differences in benzene-mediated toxicity. More importantly, this study supports the hypothesis that benzene may mediate its toxicity through ROS-mediated alterations in the c-Myb signaling pathway.

Wan, Joanne [Department of Pharmacology and Toxicology, Queen's University, Kingston, Ontario (Canada); Winn, Louise M. [Department of Pharmacology and Toxicology, Queen's University, Kingston, Ontario (Canada) and School of Environmental Studies, Queen's University, Kingston, Ontario (Canada)]. E-mail: winnl@queensu.ca

2007-07-15T23:59:59.000Z

450

Effects of low-temperature catalytic pretreatments on coal structure and reactivity in liquefaction  

Science Conference Proceedings (OSTI)

Low-temperature catalytic pretreatment is a promising approach to the development of an improved liquefaction process- This work is a fundamental study on effects of pretreatments on coal structure and reactivity in liquefaction. The main objectives of this project are to study the coal structural changes induced by low-temperature catalytic and thermal pretreatments by using spectroscopic techniques; and to clarify the pretreatment-induced changes in reactivity or convertibility of coals in the subsequent liquefaction. This report describes the recent progress of our work. Substantial progress has been made in the spectroscopic characterization of structure and pretreatment-liquefaction reactions of a Montana subbituminous Coal (DECS-9), and thermochemical analysis of three mw and reacted bituminous coals. Temperature programmed liquefaction has been performed on three low-rank coals both in the presence and absence of dispersed molybdenum sulfide catalyst. We also performed a detailed study of the effects of mild thermal pretreatment -- drying in air and in vacuum -- on thermal and catalytic liquefaction of a Wyodak subbituminous coal. Important information on structure and structure transformation during thermal pretreatment and liquefaction reactions of low-rank coals has been derived by applying solid-state CPMAS [sup 13]C NMR and flash pyrolysis-GC-MS (Py-GC-MS) for characterization of the macromolecular network of a Montana subbituminous coal and its residues from temperature-programmed and nonprogrammed liquefaction (TPL and N-PL) at final temperatures ranging from 300 to 425[degree]C in H-donor and non-donor solvents. The results revealed that this coal contains significant quantities of oxygen-bearing structures, corresponding to about 18 O-bound C per 100 C atoms and one O-bound C per every 5 to 6 aromatic C.

Song, C.; Saini, A.K.; Huang, L.; Wenzel, K.; Hou, L.; Hatcher, P.G.; Schobert, H.H.

1992-08-01T23:59:59.000Z

451

A sequential partly iterative approach for multicomponent reactive transport with CORE2D  

SciTech Connect

CORE{sup 2D} V4 is a finite element code for modeling partly or fully saturated water flow, heat transport and multicomponent reactive solute transport under both local chemical equilibrium and kinetic conditions. It can handle coupled microbial processes and geochemical reactions such as acid-base, aqueous complexation, redox, mineral dissolution/precipitation, gas dissolution/exsolution, ion exchange, sorption via linear and nonlinear isotherms, sorption via surface complexation. Hydraulic parameters may change due to mineral precipitation/dissolution reactions. Coupled transport and chemical equations are solved by using sequential iterative approaches. A sequential partly-iterative approach (SPIA) is presented which improves the accuracy of the traditional sequential noniterative approach (SNIA) and is more efficient than the general sequential iterative approach (SIA). While SNIA leads to a substantial saving of computing time, it introduces numerical errors which are especially large for cation exchange reactions. SPIA improves the efficiency of SIA because the iteration between transport and chemical equations is only performed in nodes with a large mass transfer between solid and liquid phases. The efficiency and accuracy of SPIA are compared to those of SIA and SNIA using synthetic examples and a case study of reactive transport through the Llobregat Delta aquitard in Spain. SPIA is found to be as accurate as SIA while requiring significantly less CPU time. In addition, SPIA is much more accurate than SNIA with only a minor increase in computing time. A further enhancement of the efficiency of SPIA is achieved by improving the efficiency of the Newton-Raphson method used for solving chemical equations. Such an improvement is obtained by working with increments of log-concentrations and ignoring the terms of the Jacobian matrix containing derivatives of activity coefficients. A proof is given for the symmetry and non-singularity of the Jacobian matrix. Numerical analyses performed with synthetic examples confirm that these modifications improve the efficiency and convergence of the iterative algorithm.

Samper, J.; Xu, T.; Yang, C.

2008-11-01T23:59:59.000Z

452

Assessment of Reactivity Margins and Loading Curves for PWR Burnup Credit Cask Designs  

SciTech Connect

This report presents studies to assess reactivity margins and loading curves for pressurized water reactor (PWR) burnup-credit criticality safety evaluations. The studies are based on a generic high-density 32-assembly cask and systematically vary individual calculational (depletion and criticality) assumptions to demonstrate the impact on the predicted effective neutron multiplication factor, k{sub eff}, and burnup-credit loading curves. The purpose of this report is to provide a greater understanding of the importance of input parameter variations and quantify the impact of calculational assumptions on the outcome of a burnup-credit evaluation. This study should provide guidance to regulators and industry on the technical areas where improved information will most enhance the estimation of accurate subcritical margins. Based on these studies, areas where future work may provide the most benefit are identified. The report also includes an evaluation of the degree of burnup credit needed for high-density casks to transport the current spent nuclear fuel inventory. By comparing PWR discharge data to actinide-only based loading curves and determining the number of assemblies that meet the loading criteria, this evaluation finds that additional negative reactivity (through either increased credit for fuel burnup or cask design/utilization modifications) is necessary to accommodate the majority of current spent fuel assemblies in high-capacity casks. Assemblies that are not acceptable for loading in the prototypic high-capacity cask may be stored or transported by other means (e.g., lower capacity casks that utilize flux traps and/or increased fixed poison concentrations or high-capacity casks with design/utilization modifications).

Wagner, J.C.

2002-12-17T23:59:59.000Z

453

Effect of thermal treatment on coke reactivity and catalytic iron mineralogy  

SciTech Connect

Iron minerals in coke can catalyze its gasification and may affect coke behavior in the blast furnace. The catalytic behavior of iron depends largely upon the nature of the iron-bearing minerals. To determine the mineralogical changes that iron could undergo in the blast furnace, cokes made from three coals containing iron present in different mineral forms (clays, carbonates, and pyrite) were examined. All coke samples were heat-treated in a horizontal furnace at 1373, 1573, and 1773 K and then gasified with CO{sub 2} at 1173 K in a fixed bed reactor (FBR). Coke mineralogy was characterized using quantitative X-ray diffraction (XRD) analysis of coke mineral matter prepared by low-temperature ashing (LTA) and field emission scanning electron microscopy combined with energy dispersive X-ray analysis (FESEM/EDS). The mineralogy of the three cokes was most notably distinguished by differing proportions of iron-bearing phases. During heat treatment and subsequent gasification, iron-containing minerals transformed to a range of minerals but predominantly iron-silicides and iron oxides, the relative amounts of which varied with heat treatment temperature and gasification conditions. The relationship between initial apparent reaction rate and the amount of catalytic iron minerals - pyrrhotite, metallic iron, and iron oxides - was linear and independent of heat treatment temperature at total catalyst levels below 1 wt %. The study showed that the coke reactivity decreased with increasing temperature of heat treatment due to decreased levels of catalytic iron minerals (largely due to formation of iron silicides) as well as increased ordering of the carbon structure. The study also showed that the importance of catalytic mineral matter in determining reactivity declines as gasification proceeds. 37 refs., 13 figs., 7 tabs.

Byong-chul Kim; Sushil Gupta; David French; Richard Sakurovs; Veena Sahajwalla [University of New South Wales, Sydney, NSW (Australia). Centre for Sustainable Materials Research and Technology

2009-07-15T23:59:59.000Z

454

A high dynamic range ultralow-current-mode amplifier with pico-ampere sensitivity for biosensor applications  

E-Print Network (OSTI)

components of white noise) are being substantially canceled in the input node due to the quiescent current substraction and the symmetrical

Zhang, Lei; Yu, Zhiping; He, Xiangqing

2010-01-01T23:59:59.000Z

455

IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 17, NO. 2, MAY 2002 283 Unbundled Reactive Support Service: Key  

E-Print Network (OSTI)

61801 USA (e-mail: gross@uiuc.edu). S. Tao is with ABB Energy Information Systems, Santa Clara, CA USA their implications in acquiring VAr support as one of the ancillary services. The paper provides an analysis markets by providing reactive support instead of real power. We illustrate the combined effects

Gross, George

456

Lipid Oxidation Pathways, Volume 2Chapter 2 Chemistry and Reactions of Reactive Oxygen Species in Lipid Oxidation  

Science Conference Proceedings (OSTI)

Lipid Oxidation Pathways, Volume 2 Chapter 2 Chemistry and Reactions of Reactive Oxygen Species in Lipid Oxidation Health Nutrition Biochemistry eChapters Health - Nutrition - Biochemistry AC26ACB856C86AFB9EC8D10FE0DBB342 Press

457

On the Elimination of Reactive Element Loops and the Useof Special Approximations in the Design of OTA-C Filters  

Science Conference Proceedings (OSTI)

Loops of reactive elements in passive filters cause a series of problems in OTA-C simulations of these structures. These loops can be eliminated in a systematic way by the procedures described in the paper. The use of special approximations in the ... Keywords: OTA-C filters, approximation, filters

Antonio Carlos M. De Queiroz; Luiz P. Caloba

1997-07-01T23:59:59.000Z

458

Enhanced fatigue and aging resistance using reactive powders in the optical fiber buffer coating V. V. Rondinella  

E-Print Network (OSTI)

Enhanced fatigue and aging resistance using reactive powders in the optical fiber buffer coating V causes a dramatic improvement in the fatigue and aging resistance both in aqueous and in constant for the surface roughening that causes the fatigue knee and strength degradation during zero-stress aging

Matthewson, M. John

459

A reactive transport modeling approach to simulate biogeochemical processes in pore structures with pore-scale heterogeneities  

Science Conference Proceedings (OSTI)

Redox processes, including degradation of organic contaminants, are often controlled by microorganisms residing in natural porous media like soils or aquifers. These environments are characterized by heterogeneities at various scales which influence ... Keywords: Bioavailability, Biodegradation, Pore networks, Pore-scale heterogeneity, Reactive transport models, Spatial distributions

Mehdi Gharasoo; Florian Centler; Pierre Regnier; Hauke Harms; Martin Thullner

2012-04-01T23:59:59.000Z

460

REACTIVE TRANSPORT MODELING USING A PARALLEL FULLY-COUPLED SIMULATOR BASED ON PRECONDITIONED JACOBIAN-FREE NEWTON-KRYLOV  

SciTech Connect

Systems of multicomponent reactive transport in porous media that are large, highly nonlinear, and tightly coupled due to complex nonlinear reactions and strong solution-media interactions are often described by a system of coupled nonlinear partial differential algebraic equations (PDAEs). A preconditioned Jacobian-Free Newton-Krylov (JFNK) solution approach is applied to solve the PDAEs in a fully coupled, fully implicit manner. The advantage of the JFNK method is that it avoids explicitly computing and storing the Jacobian matrix during Newton nonlinear iterations for computational efficiency considerations. This solution approach is also enhanced by physics-based blocking preconditioning and multigrid algorithm for efficient inversion of preconditioners. Based on the solution approach, we have developed a reactive transport simulator named RAT. Numerical results are presented to demonstrate the efficiency and massive scalability of the simulator for reactive transport problems involving strong solution-mineral interactions and fast kinetics. It has been applied to study the highly nonlinearly coupled reactive transport system of a promising in situ environmental remediation that involves urea hydrolysis and calcium carbonate precipitation.

Luanjing Guo; Chuan Lu; Hai Huang; Derek R. Gaston

2012-06-01T23:59:59.000Z